I agree it's a joke but how do you think comedians make money? lol
Most alt coins probably wont go very far but you can still make some decent money off them.
Also, pump n dump is honestly part of the crypto game, be with btc or doge, it's just another way to make money.
If you look at it though, at the beginning of April, doge was sitting at around 5-6 cents, then Elon made a tweet and by time 4/20 hit, doge hit around 42 cents then went back down and stayed at around 25 cents, then he triples it to 72 cents and now it sits at about 50 cents.
So from what I see any time he does tweet, he's going to at least double to triple the value and then after it will still rest at a very high flux. So weather you're holding doge or fallowing the pump n dump trends, until that man says to sell out it's probably going to continue to rise.
Plus, there are like 1k coins being made every minutes with Doge, so the 65% of it being in other peoples wallets it declining, but still I agree that is messed up. They did say it was all a meme anyway so no fault on them. Elon could have picked a better coin to do this with, but all in all he does kinda help other make money too, if you're willing to risk it.