Blissey has the attack power of a horsea, so that wouldn't be the same thing. Some Pokémon are obviously fit to solely be defenders. Weezing would just be average at anything he does.

Designing a game properly you meet certain expectations, you have consistency in your game. People come to expect STAB moves. Correct me if I'm wrong but in the handheld Pokémon games STAB is always an option. Consistency like that is important. You can't suddenly let that fall through because a Pokémon is "better as a defender" even though there's like 100 Pokémon that would be a better defender anyway. No matter what you do there is no excuse for dropping the STAB option. That is poor game design.

The fact that you're sure they did it at random and that you know how to design their game better than they do is both laughable in concerning.

I'm not sure they did it at random, this is why I've been asking what gives. Your explanation may be how they see it. But if Niantic has ever proven anything it is how foolish they are, how flawed their logic is, and how bad they are at programming. Congrats for being able to think like them.