I think there is not a good bounty available at this time due to which most of the time those professional managers are offline. Moreover, most of the new projects at this time are dangerous because the number of scam projects is high due to which they consider it dangerous to manage the bounty. Also, it's not 2017 and that year was the best year for the crypto revolution, so all the bounties would have made a lot of money. At that time the amount of scam project was less so any manager could manage the bounty then.
That's pretty much correct especially with how many scam projects going on right now. Some of the bounty managers are saying that they are not interested to manage bounty campaigns that pays with their tokens anymore because the chance of them to just run away or even the tokens worth nothing is ridiculously high and I support that. Some of the bounty managers would like to manage a new altcoin campaign but with USDT reward instead for guaranteed reward and I have seen some of them and it just works.