Can a Male and Female Cat be Platonic Friends without having Kittens?

if they arent fixed, no. They dont know platonic or friends. There urge is to mate when in heat.

No, that would be against nature. A kitty goes into "heat" & the male then must mate. That's nature. Their instincts tell them to reproduce. If you get them "fixed" they'll still go through some of the actions. That won't change.

Well if they're both fixed they don't have a choice, now do they?

Yes you get them both nuetered/spayed

Onlly if both of them are neutered, otherwise yu will soon be up to your eyes in kittens!

Only if one of them is neutered.

If at least one of them is spayed or neutered, yes.  

If they are both intact, kittens will happen.ALL cats should be spayed and neutered tho anyways.