But absolutely on the second point. A standard with one implementation is not a standard. Regardless of market share, in a market with three providers, if two out of three don't support something, you have no business using it. It unhealthy for everyone involved.
If those devs cared about Web standards, it would be a pure Web application, or an headless executable, system/daemon conecting to the system's browser.
This is why Electron app devs prefer NodeJS libs to Web APIs and consequently have no impact on the adoption of a large chunk of the new Web APIs (not counting DOM and CSS things because those are rarely controversial and usually broadly implemented).
So yes, those devs don't care about these kinds of new web "standards", because they don't work with them. The people who use them are the ones who are dangerous and that's almost exclusively web app authors, because they can't just pull in a native library to do the same things.