I feel like people are once again misunderstanding how Dick typically uses twitter. There's nothing new with what he's doing, other than some of his recent lamer jokes being directed at posters here. Hell, I think people continue to misunderstand his character in general, as shown by the people talking about his advice.
That's not to say Dax's lifestyle isn't mildly pathetic and he probably needs to grow up and let of the past a little bit (I understood where he was going with the homcoming king joke attempt, but it genuinely was really telling of his mindset), but Dick Masterson is literally a fictional character played for effect. It's certain aspects of Dax ramped up to 11, while others aspects are nullified. I'd agree that it's getting harder to tell where Dax ends and Dick begins, and it probably has been becoming more of an issue since he originally started participating with the IBS crowd a year or two ago, but you have to remember that most of what you see him do/say/post online is done for effect. Part of the 'charm' of Dick as a character is that he's a sarcastic arsehole that doesn't care if he looks bad while being a dick or making a joke, and that he'll turn on a dime and go into a fast and loud rage for 30 seconds then be calm and collected 5 seconds later. Just a shame that Dax is letting a few too many of his personal insecurities through recently (even though he's right about LSD, he's acting sensitive over it).
Personally I just think Dax has been partially fucked by the lockdown. He's clearly stressed out by it and making poorer decisions than usual (especially in terms of going on shows too far under the influence), and all this is coinciding during a fairly long stretch of 'meh' quality in his show and a bunch of minor controversies in a row (Mint, invoices, JLH).
I have a suspicion Dax realises most of this though, he's talked an awful lot the last 6 months about how he would do a TBPITU type show with various other people. TDS has simply become a bit stale, I guess you could say the meta that the internet likes has changed at the same time Dick AND Dax has gotten older, while some original fans have been replaced by these annoying incel types that don't completely understand the character or original appeal of Dick Masterson and treat him far too literally and actually look up to the character instead of just liking the character.
tl;dr Dax is getting older, the Dick character and Show staler, too much of his new audience (and new detractors, for lack of a better word) don't understand the joke properly, and Dax is making some stupider decisions than normal (though not as stupid or out of character as some people seem to think).