Jrpgs tend to be front-loaded when it comes to sale.
Also, as someone who is part of the Persona 5 community in social media, it's still very healthy and almost as healthy as it was on launch.
Persona 5's community is much bigger than Nier's. Both its OP on NeoGAF and its subreddit are more active, it gets tons of new fanart/fan creations everyday and there is also a modding community
And no, Nier Automata didn't stay in the top 20 for 3 months in a row. It was in the top 20 (11) in March, and then dropped out in the 2nd month (April). Only reason it went back to top 20 in May is because it got a $15-18 discount.
I'm not defending this policy, I think it's stupid and has no reason to exist. But saying that the lack of screenshots has killed its social media presence, cut its legs or stuff like that doesn't make sense at all.