It's almost like common problems have common solutions ;).

Of course they will implement framework-like features, that's inevitable. You'll still need routing, authentication, etc.

The win is that they'll implement them for their SPECIFIC use case, and only as much of them as they need, instead of having to accept the whole garbage that comes with a framework.

And you can cherry pick the best libraries for the cause, enging with even better ones that what any framework offers built-in.