I would suggest bounty managers to make a limit of accepted newbies and jr.members in campaigns. Even if the campaign uses stake system, accepting first 100 newbies and jr.members would be enough.
You may be able to advise a reputable manager like Hhampuz, Murat, CryptopreneurBrainboss, julerz12, irfan_pak10, Royse777, and some others managers to limit newbie and junior members from joining the bounty they manage. But your suggestions may be useless and ignored by some novice managers or other low ranking managers representing the project team. Maybe it would be nice if all managers implemented it and made those suggestions as local rules for themselves and the bounties they manage so that it becomes a good habit in the future.