AFAICT, they weren't shot down but destroyed on the ground.

No, they were hit by air-to-air missiles. One was hit by an AIM-7 and
the other by an AIM-120.

It turns out that the second Mig-25 was shot down after the Gulf War
ended; it violated the "no-fly" zone.

--
Fred Gilham
For what it's worth, the way I try to get through this stuff is to
realize that now I totally understand how things like the Roman Empire
or the Third Reich could have happened. If the people in a certain
society happen to be a lot smarter, richer, and stronger than most of
their neighbors, why not conquer them? It's for their own good.
--Bob Murphy