and then it gets complicated very quickly: https://jsfiddle.net/wdqjyvsu/1/
You also have still undiscovered problems: How to let people filter the options if you have lots of them (and don't say ctrl+f because it doesn't restrict the search within the element)? What about lazy-loading if you have lots and lots and lots of them?
Usability is not improved, it takes too much space now. API is even worse. Accessibility is improved contrast-wise but all the tabbing is not very friendly, and try using that with a screen-reader. It takes ages to make a selection.
I'm guessing you're trying to argue that something like a pill autocompleter is more appropriate for specific use cases (e.g. the `to:` field in email clients). And sure, sometimes some controls are better suited than others depending on the use case, but that doesn't necessarily mean that it's impossible to implement similarly complex controls by leveraging standard controls as opposed to reinventing headless behaviors on top of div soup[0]
Also: Congratulations, we collectively proved the article wrong. It says, "The browser’s built-in controls are quite sufficient". Here we see that you usually can't "just use standard controls", and even when you do, you need a lot of JS on top to make them accessible, usable, nice to look at with an acceptable API.
I'm not sure what you're arguing for then, it feels like you're just hating for its own sake. Because obviously not using standard controls and auto-including aria attributes will require JS too. Turn off javascript and CSS as you're arguing for, and then come back with a proper working implementation and then let's talk :)
<details> is pretty easy to style and shouldn’t be to complicated to add extra features like filter fields by search etc.
...And then to make that drop down pretty, and the checkboxes look neat, we'll set their opacity to 0 and remove pointer events, use CSS to style the label and set a nice looking tick using the 'before' content, which changes when the checkbox is selected... And oh, there again!
