The question is no longer whether they work, but why more developers haven’t embraced them.

Anytime it's attempted, someone tries to scare them into thinking that their code will impossible to maintain without a framework to provide "structure"

Because people are discussing different things.

We need to talk more about pages vs applications, web compnents are an excellent choice for making pages more maintainable, but without support for somehow automating translion of internal state (often data in a machine suitable format produced by an API) to visual state (for human consumption where said data might be scattered or otherwise recomputed) then you do run into the "maintainability" issues as soon as the visual state needs to be updated by user updates to the more machine near data model.

I see it a lot with people who ask for help about learning python.

According to the people "helping" them, before writing any line of code you should learn about ruff, uv, pip, venv, black, isort and so on… I guess most people aren't good at imagining other situations than their present one.