> In fact, custom building specific purpose code is far more attractive than it ever was. Why do I care how widely used a library is if it serves my use case perfectly? Historically, again, you had to wrestle with library conventions and styles just to get something to work. Now you can have a microoptimized library built _exactly_ for your use case.

Sounds like OP and you mostly agree on this, although you both make the same point in different ways. If everyone is building specific internal libraries, no library is going to take public traction like it used to happen. But yeah I agree with you that now specific internal ad-hoc tooling is much easier to achieve also for small shops than before.