As I was highly skeptical of the official cassette non compatibility claims, I went a head and bought a eagle compatible cassette. I measured various different parts of the smallest and largest cog as well as the gap spacing of the teeth and found that for most parts its less than 3% difference between the AXS cassette and the Eagle compatible one.
Went ahead and install the cassette (11-32t) and the SRAM AXS Red rear derailleur shifted no problem. So for those thinking of buying a trainer cassette, you might save a couple of bucks getting those aliexpress 11-32t 12s ones.