You're right and this is the criticism I have of Yang, though I supported him. I'd rather have a higher VAT and other methods to gather revenue than through deficit spending. Especially since it is inflation tied and deficit spending leads to inflation.
Though I'm also not an economist and lots of economists seem to like deficit spending. So I'm just going to say I'm naive here.
I appreciate your perspective. The problem of course is that a higher VAT would also reduce the effective purchasing power granted by the UBI.
I get that one of the benefits of UBI is that it's supposed to empower people to use the money in the way that satisfies their needs best, rather than rely on inefficient bureaucracies to determine what needs are worth subsidizing and who qualifies.
The problem is, there's no free lunch. It seems to me like any sensibly funded UBI is going to probably negatively impact many middle-class folks. Politically that's just a non-starter in the U.S.
While you're right in that a higher VAT __can__ reduce the effective purchasing power, it doesn't have to. 1) Yang's VAT was at 10% which is under half the rate of most of the European countries. So I'd feel confident that we could follow similar procedures, which would halve the deficit spending (if the carbon tax was doubled to $40/ton, there'd be a surplus). 2) VATs don't have to be applied uniformly. I'm also not opposed to a wealth tax. But from my understanding, it is harder to avoid a VAT. This is probably an easier loophole to close (and Republicans like consumption taxes, so easier to pass). But you are right in that things would need to be reformed dramatically to actually capture a wealth tax.
I still do not buy the argument that a UBI will be shouldered by the middle class. I have yet to see evidence that it will be shouldered by anyone but the 1% (really the 0.01%).
Though I'm also not an economist and lots of economists seem to like deficit spending. So I'm just going to say I'm naive here.