We are are group of people who absolutely ignore the campaign that does not guarantee a predictable reward. I may have joined a few in past but for last two years, I haven't joined any campaign that does not limit the number of users or guarantee a fixed price of token that could be precalculated. They might be a difficult to find but there are plenty of them.
You are right, just like Ludena protocol bounty that you are currently promoting, some bounty managers still listen to their fellow bounty hunters when many people are joining, some of ARCS campaigns are closed due to many people joining but still it's better to make bounty managers realize that limited participants is better, most expecially now that we have too many hunters on this forum