I think it's hilarious how much Goku talk there has been lately. First there was the whole Walking Dead x Tekken incident, then there was a crazy reveal at the end of the last the direct that left everyone asking "how could they possibly top this"? People who never thought the idea was even worth considering are now actually scared that Goku might actually happen now.
Honestly though? If he made it in, I think most people would get over it. The idea of Smash being a celebration of gaming is just kind of a title we've slapped onto it. Before it was the "celebration of Nintendo featuring Sonic and Snake", and any character not tied in with Nintendo was immediately shot down for that. But then Cloud happened and most people just learned to accept it. You've got to remember that when Smash Brothers was first conceived, it was as a new take on the fighting genre, not as a massive video game all-star crossover. It just kind of naturally evolved into that.
And honestly? I think Goku would actually be pretty hype, and this is as someone who doesn't really care for Dragonball or its characters. Heck, I barely even like most anime. But he's just so insanely flashy and over the top that it's hard for me not to see the appeal of having someone like him in Smashbrothers.
And just to clarify, I don't think Goku is ever actually going to happen. I give it maybe, I dunno, a 0.2% chance even in a best-case scenario for him where he scored #1 on the ballot. But I really don't think we should be horrified of it if it does happen. He'll still only be just one anime character in a game that still has over sixty Nintendo characters. His presence won't somehow ruin the spirit of Smash Brothers all by itself.
I actually work at Nintendo and Goku is going to be revealed in a Direct in November (with Naruto as an echo fighter). I'm just trying to prevent the inevitable fan riot before it even starts.