What you are ignoring (and in a pretty condescending way if I may say so) is that the best allocation of limited resources in the interest of users is not always to create scores of native client apps and device integrations. It's not all laziness.
Sometimes it's politics (I had a colleague leave a job because the new director of development mandated they rewrite their flagship enterprise apps in React Native because he got a song and dance from a React Native trainer/consultant and wouldn't listen to the people who knew what they were talking about).
Sometimes it's different priorities (a meetup buddy of mine some years ago had to write apps in PhoneGap because "We're in the oil bidness, not the app badness").
It isn't always "the best allocation of limited resources", either. Apart from having to do extra work to make the UX close to native (which isn't trivial), using a "cross platform" solution means you've just included a giant third party dependency that you don't control or maintain. Call it FUD if you want to, but in the forty-odd years I've done programming/development that's never been a good bet. If resources are really limited, the best bet is to have a decent design and very clear (reasonable) expectations and pay someone good to execute them.
I still mourn the loss of Windows Phone (aka one of three mobile OS choices) because of the "app gap". Small developers wouldn't invest the time or money into porting their app to the small marketshare. Even worse though, large companies would let their apps flounder, if they had one at all; the Bank of America app was simply disabled rather than being updated.
If the PWA concept had caught on, users on all platforms would have an equally good UX, increasing user choice.
