Thr rise in the numbers of scam project in 2018 made people to think that there was no future for bounty any more. But that is not true with a good project and effort invested in it you can still make a living out of bounty
Yes, I agree with you that most of the bounty hunters left hunting! But at this moment, some good and established project launched their bounty like the Populous World, CyberMiles, Eterbase and so on! So, If someone tries hard to find a reputed bounty, they can get good rewards! But the bitter truth is, we have a very few options now! The numbers of the good bounty are very rare!
Some of your listed bounties above are not new and if im not mistaken some of them are already published last two years ago but i dont know maybe they reset a new bounty ? . there are still bounty hunters that continues to do bounty hunting and some are only doing a trial and error . thats the best thing that they can do if they desperately want to make a living off thru bounties .