Most Xbox360 and PS3 games were 720p at 30fps. 720p was mostly fine because 1080p TVs were luxury items back then.
The performance problems in modern games are often not caused by fillrate-vs-resolution bottlenecks though, but by poor engine architecture decisions (triggering shader recompilations in the hot path).
The performance problems in modern games are often not caused by fillrate-vs-resolution bottlenecks though, but by poor engine architecture decisions (triggering shader recompilations in the hot path).