How long would you say a properly installed panel from 2000 made it in practice? How long would the modern equivalent installed in 2025 be expected to make it? And how many replacement events does each of those make for over the course of your life?
Do you contest my earlier claim that solar is roughly equivalent to wood siding or an asphalt shingle roof?
Using 30 years as a lifetime for solar panels is risky as there are no solar panels running for 30 years, not even close. Never mind the lifetime of the power wall battery and the inverters.
I bought a 40 year "premium" asphalt roof. It barely made it to 20. A regular asphalt roof, perhaps 10 years. Now I have a metal roof.
All the results I've seen indicate that solar panels will keep producing electricity long after those 30 years, just at a reduced rate (but seemingly still >50%).
I'm not sure what kind of answer you expect here. Your initial objection further up was:
> By the time the "free" electricity has paid for the installation, you'll need to replace it.
Since you won't need to replace it, I'd say that this whole thing couldn't work out better: the panels are literally just generating electricity for free! And that's not even taking into account that 30yo panels generate more than "only half the power" (the study I linked measured ~80%).
Imagine someone offered to give you their 30 year old panels and install them on your property for free. Unless every eligible surface is already taken up by more efficient solar panels, who would say no?
Source: my experience
Roofers also tend to regularly close their businesses and open under a new name, so they don't have to honor any longevity warranties.