Issue bankruptcy is real. Speaking from personal experience, at some point maintaining OSS is incompatible with living in the real world. The work is free and often thankless (but not always). The problems are complex and compete with real world responsibilities, like work, family, rest. People get pissy and regularly want to argue with you or read the docs for them. It also carries enormous responsibility if your OSS is popular.
I am anticipating a huge collapse in the OSS ecosystem as the people who drive them say "fuck it" and walk away for more important things.
That I can understand. These days I'm almost starting to think of nontrivial personal projects as more an addiction or self harm than real projects.
The OSS ecosystem is insanely inefficient though. There's lodash, underscore, and plenty of others. They don't all need to exist. There's also lots of libraries that only do one thing, which are mostly a subset of something like this.
Most of this stuff will be used with minifiers and tree shaking, and unused features will be removed, we don't need lightweight libraries when the heavy ones are easily optimized and mostly made of separate parts, so the dev effort mostly scales linearly.
I think OSS has plenty of manpower, even if everyone decided to only spend a quarter of the time they currently spend, if it weren't for the fact programmers like elegance and simplicity more than anything, and constantly want to rewrite to make things just a little bit better.
I am anticipating a huge collapse in the OSS ecosystem as the people who drive them say "fuck it" and walk away for more important things.