"have scientific journals disappeared" -- ironically, in the AI field most of the action is on arxiv / github / twitter. journals have been obsolete for decades, and the '10s obsoleted conferences too. the only function journals / conferences still serve in the AI field is to stack rank researchers and provide signal for hiring / funding decisions.
Anybody can publish anything with the web. Have publishing houses disappeared? Have scientific journals disappeared?
The insanity is doing the same thing over and over and thinking "this time it will work".