Why can't Mario fans and sonic fans get along?

It's all about opinionated people. they are arguing because they are just little kids who don't know any better. they can't even help it. they have to defend sonic/mario. so the argument is caused by the person who is the more obsessed. idk. they will go on and on about it. and it usually drives the other fan crazy. and he thinks sonic or mario are greater. so it conflicts and makes them fight to see who is better. it's a bit confusing. but yep. it's stupid. none of them are better than each other.

I know right i hate the debating! Sure im more of a sonic fan than a Mario fan but i still like both

Yes

Because back then, you couldnt have the Super NES and the Genesis. It was one or the other. After Sonic fans heard that the war to end all wars was delt with, they went all balistic. The second they found out the Super NES sold 23 million consoles in North America and the Sega Genesis sold 20 million consoles back in their hayday, they wanted to start another war which led Sonic and his franchise downhill. (you can thank senior Sonic fans for that) Then the whole world went against him because, like Mario, they wanted all these gimmicks like swords and werehogs, but the difference was that Mario pulled off gimmicks cuz his whole franchise was build on gimmicks and power-ups. Then Sonic Colors came and things have been better for him ever since. Mario fans dont like to admit that in richer and essence categories, Sonic wins. Sonic fans dont like to admit that in quality and "deja-vu" categories, Mario wins.

i wounder how they react with the games that they team up in

This.