But if you read the piece you’ll note:
Browsers have been experimenting with variations of this since at least IE7. Implementations vary a bit, and browsers are still trying to strike the right balances, but overall the idea is consistent and works well: A couple of billion mostly unaware folks using Web browsers for the last 8+ years have proven it out.
In other words – the web actually does work this way “out of the box” and it works that way because of years and years of user-feedback and testing. I’m not sure how you could make the statement that this is encouraging apps or users anyone to live in one mindset, this is about responding to the fact that there isn’t one. The issue is that: a) “out of the box” styles frequently don’t work with designs. If there is a native outline that is blue that works fine on a white background - but maybe your site has things that rest on a background that is blue and it doesn’t. The Web today gives you levers and switches to tweak this, but in doing so all of the lever options are nuclear - they break the “out of the box” behavior. b) There’s no good plan for things that don’t already come in the box - if you make a new component - or in my brightly envisioned future you import and use non-standard but competing ‘slang’, there’s no good/reasonably simple way to get them to play nice.
The proof here is that lots and lots of pretty web smart folks have tried (and often failed) to solve this problem independently, have a look at the twitters and articles like Marcy Sutton’s Button Focus Hell. These are not new authors who are missing a simple thing about the Web, this problem is frequently evident in things built by frameworks and libraries that build the foundations of the Web today.