That’s one trend I hope doesn’t spring up over here. I hated the fact that 95% of the subs on /r/all were literally the same thing. Like, what was the difference between MadeMeSmile, DamnThatsInteresting, NextFuckingLevel? Just all the same clickbait trash, and then, as you say, some “organic” marketing campaign for the latest Marvel movie.
Edit:
Mastodon handles this by not having an algorithm. In order for a toot to gain traction, it actually needs to be boosted around so that people can see it. A great example of how this prevented “organic” marketing was with @Raspberry_Pi.
When they first joined, their SNS team tried the same easy brand tactics that they used on Twitter, trying to force engagement. It had the opposite effect, and the community backlash was fierce. They have since changed their messaging and become more genuine.
Since link aggregators usually need some kind of algorithm for a “front page,” I think the most important thing is to have it be transparent and static. No changing it every 4 months to increase engagement.
Most importantly, the community should also have a shared opinion on what kind of stuff they are okay with, and this can be more localized per instance.