tbh hackerone should just implement a +/- reputation points feature on researcher profiles. Like, the researcher submits a slop report to GitHub via H1, GitHub looks at it and identifies it as slop, GitHub presses the -rep button on reaearcher profile which bans them from submitting to GitHub on H1 again and makes their rep points minus 1. Companies should be able to configure you need at least 10 rep points to receive payouts. Only specific (by H1 chosen) companies can +/- rep.

So, researchers first need to collect some positive rep. But the rep points are global, so once you have fixed a few bugs for Google, you've gotten enough +rep that you can also receive stuff at GitHub.

Oh, and ID check when signing up at H1.

Long term all beg bounty submitters would be banned for pretty much all of tech.