Learning programming isn't so much about the language as it is about human beings and motivation. While language enthusiasts are very excited about type systems and technical details like syntax, what beginners need is to get over that initial threshold and to be able to self-motivate.
The first question to ask when choosing a language is: is it useful for practical programming? Can the students do something that feels like an actual accomplishment within the first week? If it isn't, then you can't use it as a beginner's language because it has a weak reward mechanism. The reward is to be able to solve practical problems that mean something to the student. And this is critical in the initial weeks and months.
Printing a fibonacci sequence is not rewarding for most students. It is for some, but in my experience, not most. Printing a fibonacci sequence with tail recursion even less so because a student will have no idea of why this may be important.
Being able to write a program that meaningfully communicates with its surroundings to do work IS inspiring. Whether it is consuming input from the outside and doing something with it, blinking a LED, making an HTTP request, or sending a message. (Or in the case of my nephew: write a Discord bot that honks a horn when his friends are online and try to get his attention. Which didn't just solve a practical problem: it gave him status among his peers, which is a strong motivator)
For instance: I tend to recommend Python as a first language. I don't like Python myself, but I recognize that it a) allows you to do practical things, b) it has a relatively simple syntax, and c) it doesn't really force a lot of fluff on you that "this will make sense later". It also allows you to postpone topics that initially just confuse students.
Java, JavaScript, C, C++, Lisps and perhaps more esoteric languages are for later. Yes, I know people think some of these are "the right way" to start, but that's often the teachers focusing on their own interests and not focusing on the student. Bad teacher.
Let's get people over the first couple of hurdles first, and then we can talk about what's next. But you always have to remind yourself that introductory programming is about humans.
I am a big fan of showing two languages at the start. Statically typed Java/something so that the idea of data types is ingrained. Then rapidly switching to Python after the first lesson.
A real problem I've seen (and had) with absolute beginners doing Python, is they really struggle with the types of abstract variables for the first little while when they're "getting stuff done."
"Knowing" to use type() to debug your programs isn't something that comes intuitively to a novice who's been programming for all of 25 minutes, They have absolutely no idea that builtin is there or they need to use it.
A quick Hello World in something with static types, and a "tour of data types" can go a long way. Also helps sell them on Python.
I wonder if Typescript is suitably fun for this. Because I'm convinced that a significant part of the attraction of Python to beginners is pure aesthetics.
I am not entirely convinced you need to worry too much about types in the sense we think of types. Sure, people have to have a basic understanding that there are different kinds of data, and that multiplying banana with poem doesn't make sense (well, actually, in Python it has an interpretation, so that was probably a bad example :-)).
If your program has to figure out what type some variable is before operating on it, I think the aspiring programmer has already overcome the first few barriers and is already tackling a more advanced subject.
I think initially the understanding that there are different classes of values you can assign to variables and that getting these confused can produce unwanted results is a very good first insight. And when that settles in the students mind, they might be receptive to "then there's this family of languages that get really particular about what goes where".
(I also think it is important to try to not involve too much technical terminology early on. Have a look at Richard Feynman's lecture about the double-slit experiment and note how he uses absolutely no technical language. It is so well done it didn't even occur to me until after I saw the talk)
Probably biased here, but back in the days before frameworks I found plain PHP with HTTP a good case of explaining, out of necessity. Every variable arrives as a string anyway and you need to check if it's actually an integer if you want to use it as such (let's ignore weird autocasting).
On the other hand I'm not sure it's teaching a good lesson here, because you're simply taking the un-typedness of HTTP parameters as an example, whereas in other environments you would simply explain there are number data types and strings and others...
I recommend JavaScript in the context of plain HTML as a language for the first steps in programming (especially for kids). Being able to write a simple HTML file and then see things happen immediately on a refresh is priceless.
I wouldn't say that JavaScript is necessarily an "easy" language. I think what you're after can easily be accomplished in most languages that have a REPL or equivalent (including interfaces such as https://play.golang.org/)
Not having used JS for teaching someone how to program I'll take your word for it. It may be that JS only gets complicated when you try to make non-trivial software (and then things get complicated in a hurry).
I'm not sure how important 2 is. Installing VS Code and a handful of languages isn't all that hard. And it is just relatively quick setup.
The first question to ask when choosing a language is: is it useful for practical programming? Can the students do something that feels like an actual accomplishment within the first week? If it isn't, then you can't use it as a beginner's language because it has a weak reward mechanism. The reward is to be able to solve practical problems that mean something to the student. And this is critical in the initial weeks and months.
Printing a fibonacci sequence is not rewarding for most students. It is for some, but in my experience, not most. Printing a fibonacci sequence with tail recursion even less so because a student will have no idea of why this may be important.
Being able to write a program that meaningfully communicates with its surroundings to do work IS inspiring. Whether it is consuming input from the outside and doing something with it, blinking a LED, making an HTTP request, or sending a message. (Or in the case of my nephew: write a Discord bot that honks a horn when his friends are online and try to get his attention. Which didn't just solve a practical problem: it gave him status among his peers, which is a strong motivator)
For instance: I tend to recommend Python as a first language. I don't like Python myself, but I recognize that it a) allows you to do practical things, b) it has a relatively simple syntax, and c) it doesn't really force a lot of fluff on you that "this will make sense later". It also allows you to postpone topics that initially just confuse students.
Java, JavaScript, C, C++, Lisps and perhaps more esoteric languages are for later. Yes, I know people think some of these are "the right way" to start, but that's often the teachers focusing on their own interests and not focusing on the student. Bad teacher.
Let's get people over the first couple of hurdles first, and then we can talk about what's next. But you always have to remind yourself that introductory programming is about humans.