If you are trying to commercialize something, a popular project with bad margins is a better spot to be in than an unsuccessful project with good margins. If it's a personal learning project, that might not be the case.
These cloud back and stacks are very cheap at low volume and honestly I expect them to remain so or even go down in price.
I've seen many colleagues bootstrap something - even if they're not themselves very technical - because they've leveraged these well integrated low cost platforms.
I do think it’s binary. The project either shows potential to meet your goal or it doesn’t.
I think it’s rare that fails to show potential because of the underlying technology that’s chosen.
Sure, Vercel is relatively expensive. But I just don’t see how you’d throw in the towel because the costs are too high without first evaluating how to lower them.
If you’re saying that the evaluation is likely to show that you’re stuck - I have never seen that be the case personally.
An unsuccessful project might be unsuccessful because it got eaten by costs before it became successful.
A wildly successful project is risky to migrate.