I can tell you what started me realising I only really wanted to be with poz men. The first man I was ever with was a bit older than me and one day he got serious and asked me how I would feel if I found out I was talking to a positive man. Would I love him just the same, or would it be an obstacle?
I told him it wouldn't. Tbh I thought he was going to tell me he was poz. Anyway, he said I was disgusting and he could never be with someone like me and ditched me. I realised the only way to avoid an anti-poz bigot was to prefer poz men, and that I owed them complete and total acceptance.
If I was with a poz man, I'd never ask him to use a condom as though I didn't want him to touch me. My need to please him would never be less if he was detectable. It seems cruel to say "I want you, but only while you're undetectable". So to me none of the dialogue around detectabilty and infectiousness matters because either I'm his or I'm not. I think a neg guy who doesn't want to be with a poz man, or only on certain conditions, isn't really worthy of him