I had no idea that he died of AIDS and that was in the 90s. It's terrifying how recent it was that he would have received public backlash for contracting a disease during a surgery.
I feel like you're leaving homophobia out of the equation. Asimov was ashamed, and there would have been a backlash, because society associated AIDS with gay men. If people had really believed that he'd got it through surgery, there wouldn't have been a bad reaction.