>>58634178Hitting hard isn't the only way to win games. Bug has 2 major things going for it:
>Decent suite of resists with few weaknesses>STAB U-turn (as well as every Bug getting U-turn), the best pivot move in the game and an easy contender for top 10 non-signature move in the games.These alone, particularly the lack of crippling weaknesses giving it a decent defensive profile, put Bug above Rock and Ice. Sure, Rock and Ice are better offensively, but they're so much worse defensively that it's no contest.
Forretress vs Ferrothorn isn't as simple as you make it sound. Ferrothorn has a significantly better ability and significantly more special bulk in exchange for not being as physically bulky. It also has a better movepool than Forretress. And yet Forretress is still hanging on to competitive relevance alongside Mew, Gengar, Jirachi, Magnezone, and Blissey. Forretress simply got powercrept - it's by no means a bad Pokemon.