I don't hate it in itself, and I think some AGA games look amazing (Ruff 'n' Tumble springs to mind as an example).
Ruff 'n Tumble runs awesome here on my OCS Amiga

As well as Lionheart, Elfmania, Jim Power and Fighting Spirit.
That's why AGA feels a bit like a let-down, the best looking Amiga games are all OCS original.
There's one very valid pro-aga point however, Doom needed a lot of megaherzes and megabytes, also on the pc (or a 3d accellerated chipset like on the Playstation and Atari Jaguar).
I remember that Doom didn't run smoothly on a friends' 486 66mhz with 4mb memory. Neither did it run smooth on my 486 33mhz with 8mb. It was all choppy and I have tweaked alot in my bios and config.sys/autoexec.bat to enable it to run that tiny bit faster (to a point that the whole system seriously crashed). I don't know whether it even ran at all on a 386.