Maybe that's because AFAIK the various frameworks out there for building applications are strongly opiniated on a given paradigm. We have libraries, but we don't really have composable components that can be assembled into arbitrary architectures.

It's like we're stuck assembling applications by stacking pre-existing Lego sets together with home-made, purpose-built, humongously-sized Lego bricks made of cardboard acting as glue.

I've ranted a bit about that here: https://news.ycombinator.com/item?id=34234840