I have asked the question Distinguishing RPi4 models with USB-C issue and without (probably only visible for users with enoughrep) on January 8th.
At that time, it was downvoted and eventually deleted by Community♦ a month later.
To me, it seems that the question is perfectly valid. And I now found evidence that revision 1.2 of the board was already known about in November 2019.
I would like the question to be undeleted, so I can self-answer it. I already clicked on the "undelete" link, but it needs more votes.
I'm posting this meta question, because I can't post such a long reasoning in the moderator's flag.