aatrox was never a strong pick

They prob didn't see his lvl 2 tower dive rampage in pro scenes before.

I guess the main issue people have with him is him being an auto attack based life-stealing carry/tank; I don't think there's really a good place for that in the meta. I still think he's awesome but he gets outclassed I think

Probably because his kit is boring (although not as boring) like tryndamere's.

He is an AA based champion with minimal sticking power. He pays very hard for his passive which is only useful in tower dives. (if enemy procs your passive in 1x1, you will most likely get killed, or enemy will escape) He has very bad defensive stats, which he needs, because he's a melee. Heal is a double-edged sword. You get harassed- you have to heal- you heal you kill minions, lane pushes. E projectile is slow, cast time is long, projectile width almost non-existent at max range. Almost impossible to hit from mid range. Q cast is slow, uses 10% of health, can be stopped, cc'd, evaded.