Okay, so based on PBA’s post, I concede that it was in fact Avak Lashon Hara.
Let me correct the record. A legitimate question asked in a sincere way would not upset him in the slightest (I don’t think). The narcissistic stupidity of the antivaxxer movement is what upsets him.
I have engaged several doctors on the subject, and I have never encountered resistance to an open discussion of it. I have never personally experienced, nor even heard of, a doctor saying anything like, “If you even try to delay vaccines we will not take you as a patient.”