I use the legacy "File New" interface. In Illustrator 25.2.3, when you specify a page width of 8.5" and a page height of 11", Illustrator automatically selects the Landscape orientation button instead of Portrait like it should. And if you select a page width of 11" and a page height of 8.5", Illustrator selects the Portrait orientation button instead of Landscape like it should.
I can always press the correct button before I hit OK, but I shouldn't have to.