>>16460210They kinda really are. Samurott is probably the most usable of the three, because Masuda will not let a shitmon be the face of the Water-type for any prolonged amount of time.
Emboar... has a diverse movepool... but its STABs are so self-destructive (and its speed is so low) that it actually can become a problem IN GAME.
Serperior is damn near unusable. Low-to-underwhelming stats in everything but Speed and a Flareon-tier movepool to boot. Ironically, it would've been OU if Contrary was ever released. And we'd be wasting half of this thread bitching about Smogon Snake.
All of the Gen V starters were deliberately made weaker than those of previous gens. The point was to encourage players to seek out and use a wider variety of Pokemon, facilitated by the radically altered experience mechanics which favored raising weaker 'mons over continuing to rely on your main.