Hi,
This is not true - PS2 Linux provided full hardware access to the graphics hardware via the SPS2 library, which just mapped a bunch of hardware registers into your userland address space.
The IOP chip was restricted but that wasn't really a big deal for most purposes, as it was generally only used for I/O.
The IOP chip was restricted but that wasn't really a big deal for most purposes, as it was generally only used for I/O.