Should dating be exclusive before a relationship?

I've previously been burned by "situationships" that benefited from all the perks of having a girlfriend without the actual label/commitment.

Since then, I've gone off the idea. I would rather be in a relationship, or not in one. And I don't like the idea of being exclusive without a proper relationship tag as well. (I get that this works for some people though)

What do you think? Would I be an asshole for insisting this with future partners/saying that I'm not interested in dating exclusively until we want to be in a relationship?

Edit: I'm having a weird love triangle situation where I really like two people - and I don't know what to do!