I've been pretty much on this side of the argument. When I've seen the work that goes into designing a framework even one that I generally have little love for like Next.js, but still appalled by things like vinext. Atleast there I get the platform tension. But a library or tool without its vision is doomed to fall apart. Its the same problem as compat. Either you reconcile yourself to always follow the others vision or you admit it is stopgap migration strategy. It's not a long term plan.
But, step back and think about this as an entrepreneur. Ie.. build it and they will come. You are supposed to throw as many ideas against the wall and see if they stick. I see the danger here in leaving rotting carcasses of projects in its wake. But at the time of building there is every intention of supporting them if they are successful. If they are successful, is the distinction. What's crazy to think is how low the upfront cost is to do this. Our measure of how to trust a project completely changes. However, our cost of migrating solutions is also cheaper than ever so is it actually that expensive? If Vinext proves a dud you can always go to Next.js or maybe something else.
I guess what I'm saying is capitalism has been a part of OSS for a long time. We like to think of it often as this communal thing, but we've had Microsoft and other large players dictating the shape of this for years. AI is actually democratizing this in a sense. In a sense it sucks for the smaller players, I think it risks snuffing out real innovation. But on the average we just put bigger capability in everyone's hands. A single maintainer can move mountains with the right product.
Honestly it is terrifying as a smaller player myself, but I don't think this just amplifies what was already happening. OSS has been struggling for years. Maybe this puts the nail in the coffin. Or maybe this points to the way forward. Or most likely this is just the new balance between both.
What Theo is doing here is actively harmful for OSS maintainers. This behavior just causes people to say "if this guy can do X why can't you do Y". But vibed rewrites are completely useless unless you plan to support them.