As much as the word gay can just be a descriptor language likes to flip the bird at that kind of thing and people end up using it to call out people who are gay that and the matter of people dont like gay people so they can contextualise gay as an insult.
As for saying retard well I mean you cant be surprised that a word to insult the mentally ill insults mentally ill people and people in general.

I'm saving that pun for later and I have no idea what scenario i would use it in

Hmm yeah I get where your coming from now

Well that isn't a gross oversimplification

Well if your not homophonic and other miscellaneous why would you have to keep reminding yourself that. Not that I'm accusing you of such but if it ain't a problem your suffering from why worry