First it was Seunghan being kicked out, then Jaeil, then Taeyeon and Wendy, then Key collapsing on stage and having to leave early due to health issues. Then the Taemin thing plus him not being in the 30th anniversary photo shoot for SHINee.
Bigger picture, I don’t think we can see any clear signs of a “downfall” yet. Probably won’t be able to see any possible indicators until after the next gen rolls out.