DXT1 is BC1, DXT3 is BC2 and DXT5 is BC3. No one really calls them DXT and they aren't used much today anymore but I went along because you called them DXT

If you are still using DXT to describe them, you should check out BC7 for instance which gives extremely good quality on the compression rates MS talked about and BCPack should be an upgrade over BC7.
Regarding compromises, You don't have to compromise in quality, you can compromise in delivery time. If the PS5 can stream in extra detail for the asset in 33ms, what's stopping the XSX streaming the same in 67ms? Yes, it will give it a delay of 33ms, and extremly quick pop-in that morphs in, but will it be actually noticeable when it takes 33ms? I have no idea, I guess we will have to wait for DF analysis for that one.