People don't like the idea of Toad being a playable character because there are far more deserving characters who do more than spend time being a useless castle guard.
GRRAAAGGHH!!HOW is Peach more deserving? She's just some dumb blonde that gets kidnapped all the time! How is Bowser more deserving? He continues to kidnap the dumb blonde and somehow think that his latest plan is going to work. How is Zelda more deserving? She spent the first half of OoT
in the castle, then the other half hiding from Ganondorf, only to be kidnapped at the very end. How are the Pokemon even fighting?! They need trainers to tell them 'do this move, do that move..'. They don't even fight in the wild.
I am sorry, but there are not that many more deserving characters left. Toad should have been in at least the second game..
How is Toad weak? In SMB2, he could pick things up the fastest out of the four characters. The game has been remade at least twice and they've had ample opportuninty to change things around, but Toad is still the strongest. In Wario's Woods, Toad could pick up entire stacks of bombs/aliens and move with them (and kick other bombs/aliens while holding the stack). In all the Mario Kart games, Toad is among the fastest and often has the best traction (Mario Kart Arcade aside. Haven't played that one myself..)
If Toad is so weak and useless, why do they keep giving him tremendous strength and speed stats? Pichu is weak and useless and became a SSB character anyway, and I had a hard time imagining Olimar as a playable character in SSB, so it's not outside the realm of possiblity anymore that Toad could become playable.
People don't want good characters playable. That's what it is..
