Every modern development "best" practice has, what I believe, one end goal in mind: to change computing from an active activity into a passive one. More specifically, as nothing more than an entertainment box with metaphorical guard rails. Of course this is not restricted to web sites, but since the browser is the medium everyone has settled on, it's the most egregious. I also believe that the reason it's so polarizing to those of us who have done computing for so long is because we unconsciously understand this is restricting freedoms (utility, not political) we once knew. For example, forcing things like infinite scrolling and overly-fuzzy searching is the new way of forcing channel flipping onto users, not to mention auto-playing of current media and auto-loading of related media afterward.
Another goal that I believe modern practices aim for is infantilisation of computer users. Everyone is acutely aware of this in practices like showing cutesy error messages, or software interfaces that can be mistaken for sales catalogues. However I also notice this every time any software automatically corrects something I was trying to do, and often without telling me until after the fact. I don't necessary mean a spell-checker, although this can go to far, but something like M$ software applying formatting to data I copy-paste, or Google services aggressively forcing me to use WorkAccount-A instead of asking me to choose WorkAccount-B and I don't notice until I need some resource associated with WorkAccount-A. I'm trying to use software here with intention, but you're saying you know better than what I want to do.
Also, a particular practice that I hate is Cloud Computing. Yes, I understand that terminals connecting to a mainframe is much older and is still a thing; but my problem is their aggressiveness in capturing all computing, especially data housing and collection. I feel infinitely better about renting a Linux box and rsyncing files than trying to use Cloud services. I'd rather risk losing my data to bit rot than corporate rot.
This post is autistic enough while also straying from the topic, and I could keep going, but it all boils down to what I stated above: nearly every pushed practice wants the average user to become a baby playing with Fisher-Price toys who needs to be told what to do.