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.
Actually, all bounty hunters are not dumpers but some can't hold on to a token immediately after the token get listed on an exchange.
I will advice all projects to adopt the use of ETH as a means of reward to bounty hunters, this won't affect the token value at exchange.
My take