Oh I worked on titles in that era too, and on other oddball platforms like the PSP :).
Without getting into the weeds too much you just weren't doing much with the single CPU core on the PS3. As soon as you booted anything of note it was pretty obvious that you'd have to offload to the SPUs. I'm not saying that it wasn't more work, but most of the other teams we talked with who had done PS3 as a baseline first had a much, much easier time of it.
I would say that any console/handheld developer the approach wasn't unfamiliar, but there were certainly a fair number of engines with roots in the PC space that had a rough time of it. That said it was more down to the SPUs than anything related a unified memory architecture(although we did do some fun shenanigans around streaming music back from VRAM to the CPU to give us more system memory headroom).
