Is Google classing online encyclopedias as "AI"?

I have noticed, over the past couple of weeks, that when I do general searches in Google, Wikipedia articles are coming up far less frequently than they used to. And this seems to be caused by the "-ai" I have added to be appended automatically to the search from my browser box, to stop Google wasting energy with its unreliable AI results. This seems confirmed by explicit searches from Google's own page.

To take an example: searching for 'algernon sidney -ai' (you don't type the quote marks in; he's a slightly known 17th century English figure) returns sites in the order:
oll.libertyfund.org
quod.lib.umich.edu
www.historytoday.com
www.freespeechhistory.com
radicalteatowel.co.uk
thehistorywoman.com
www.npg.org.uk
...
The first wiki page I get on him is en.wikiquote.org; the first Wikipedia article is the Welsh one!

But if I just search 'algernon sidney' I get
en.wikipedia.org
www.britannica.com
radicalteatowel.co.uk
oll.libertyfund.org
www.historytoday.com
www.azquotes.com
...
and thinking about it, Enc. Britannica results have also been turning up far less in my experience - even when I've put "britannica" in the search terms, it doesn't seem to find a decent article as often as it used to - when the '-ai' is appended. It's not just this one search, of course, but this is the one I've directly compared the results lists for. Any similar experiences, or ones that show the opposite, gratefully received.

(And no, DuckDuckGo still does not return the quality of results that Google does, so I'm not just going to switch to that)

Is this malice? A mistake? I can find that Wikipedia: AI-Generated Summaries Are Hurting Our Traffic, but that's not quite the same thing.

(Can't think if there's any better DU group to discuss this in - I'll move it if people think it should be).