Those 2 years were about comparing the Insomniac took on R2 and Naughty Dog has for Uncharted 2. Maybe it wasn't 2 years, but it's a similar time frame. But I'll leave Uncharted out of this from now on.
I was comparing R2 to Rfom, not any other games.
The SP was 2 to 3 hours shorter, it has a few less gun with half of them being redesigned versions of the old ones, and there is a negligible difference between Normal, Hard and Superhuman. So IMO, it was watered down.
The Co-op is very nice, no complains here.
Competitive suffered the most IMO. With only standard deathmatch, core control and skirmish available, and fewer options to customize your game. It falls well short of Rfom. Besides that, it has (had) countless bugs and glitches, most of which were already known during the beta, which should only have been a matter of time to fix. I know all MP games have problems on day 1, but usually not this many. Insomniac has quite a track record for delivering highly polished games, but R2 wasn't one of them.