"fall of assassins"

Nawh, not OP. Just even or slightly stronger than AD junglers. But with a tank possibly in the jungle, and maybe tanks as supports and/or top laners, it's true assassins are getting a hard time. (Though it's damn good riddance as far as i'm concerned. I prefer a game in which i know what's going on to a game in which i randomly get deleted.)

Yeah but you're missing the point. If there are three tanks, an assassin and an ADC in a team, (Typical example being Malphite Top, Hecarim Jungle, Leona Support, Jinx ADC, Leblanc mid) Three you pretty much can't assassinate at all, the assassin can assassinate you right back, and the ADC is being absolutely covered by the tanks. No matter how you look at it it's harder than if top lane is a less tanky bruiser, and/or if bot lane has a mage support.

Thing is, will you risk being useless against a tanky team, which just never happened before, or will you get lucky and hit a team with more squishies? Assassins are as strong as ever, but their relevance is highly affected by the enemy team's composition. Cinderhulk didn't make tanks all that OP, but people realized how useful they were in the assassin meta, which switched everything around all at once.

Contrary to what many say around here we are not in the "tank meta" but the "assassin/tank meta". Assassins never fell out of favor. A few were simply nerfed out of favor. The rest remain.