It looks like a normal email but has the word “Ad” in small letters. When you click it, it opens a link, rather than rendering email content in another pane.
It’s a pretty tacky design, in my opinion, even if it was only serving “legitimate” ads.
I don’t like that Apple feels emboldened to demand that laws be repealed. I don’t recall if Apple has done this in the past but it’s a shift in tone that makes me uncomfortable.