What are the rules for 100% do you have to obtain all gloves?

Or is it just like story% complete 100% if the story.

I would say that it requires collecting all gloves for sure

For sure. And clearing infinity stage?

It would make sense for the rules to be something like "win at least once in every stage and collect all gloves". And there should be then a list of all the stages and gloves just to make sure everyone know what they are.