I believe this is not a fair assessment as a lot has to do with the crypto project itself.
Its a matter of perspective really, not all bounty hunters have the same experience or motive, some people just need an opportunity to get crypto for projects that are very difficult to get in the token sales, Example is Ncash tokens of Nucleus.Vision the project has a 1 million USD budget and it is still above ICO price even in the bear market.
Additionally some projects treat bought hunters badly which will not encourage them to stick around for much longer after they get their tokens.
I believe tokens or coins getting dumped by bounty hunters depends a lot on the project itself.
In my opinion, maybe everyone is not sure that more bounty hunters sell coins at cheap prices, because doing campaigns also requires a lot of effort and time. But we also have to realize that it is easiest to blame the bounty hunter for all the situations that occur, because some people actually do it. But any situation will always return to each project, because there are many investors waiting for discount coins from bounty hunters out there.