My mother had her DC from early seventies to mid eighties @Mamanyt and she repeated the same stance you mentioned ad nauseum.
I had my first two at the end of the millennium and remember being warned against drinking at the first hospital appointment and replying that I only intended to have half a glass of champagne at each of three special occasions that fell after the first trimester. I got “a look” for that, but no contradiction. However one of those occasions was a family one and my mother made quite a scene telling me I was “damaging” my baby and it would “come out abnormal” (we are probably talking 80ml of champagne here - just for the toast). That was quite the glare off.
I don’t remember anyone medical saying much about it at all with my third ~10 years ago, maybe because I was considered an “old hand” by then? Not sure.
I DO remember my pregnant sister drinking a whole glass of red at an ordinary Sunday lunch a few years, and my mother not issuing a squeak, so I assumed someone had collared her and told her the updated guidance, which I gather was less draconian by then?
I’ve seen different studies make the news over the years but haven’t really followed the advice fluctuations closely. So I couldn’t confidently say what is changing medical research and what is a rebalancing of minor risk with women’s personhood.