Brawl is a game where everyone camps and Melee is a game where everyone spams combo starters.
Go ahead, spam a combo starter, it doesn't guarantee a combo thanks to a lovely factor called DI. Though, I play Jigglypuff, I don't get an uthrow > rest every time, because people keep holding left or right and they get out of it. And I don't always successfully follow up with a pound or uair.
Melee is a lot harder to learn than Brawl. Brawl is good for a party game. And brawl matches are often boring. If you spam a move so that your opponent can't space right to hit you, then spamming wins. Doesn't take long to learn a good spam.
In other words, I hate Pit, and i hate MK. But my friend Opal likes Brawl because he can spam pit and beat me like that. So I have to go Ness and Lucas on his ***.