Oh well... I guess linux is better for moving foward with X, even if it breaks old stuff.
I spent a while writing Windows 95/98 video drivers; we had a mix of 32-bit assembler and 16-bit C code in a 16-bit driver being called by 32-bit applications through a 32-bit to 16-bit kludge layer and negotiating with the 32-bit 3D drivers for control of hardware, all for the sake of backwards compatibility. Only the switch to XP finally eliminated that abomination.
So yes, I'm glad that Linux devs are willing to break things if it results in a better end result. Unfortunately of late they often seem to be breaking things that remove useful functionality that we've been used to for years (Unity, Gnome 3, Wayland, etc).
Did AMD even have AGP at that point? If Intel had a cheap 3D card because it didn't need much memory, and it required AGP so it couldn't be paired with non-Intel CPUs (if that was the case, i don't remember when non-Intel motherboards got AGP) then it could still be a win for the business even if it was lousy for games.
That was the day of the K6-2, and yes AGP was around for Super Socket 7. My first build was a K6-2 and Trident 6326.