In fairness, Source/HL2 also got many engine patches, including HDR, and continues to. There was also Lost Coast, and the fact that Source could run on surprisingly crap machines.
That, and Far Cry just wasn't as involving. I played it, and I really liked it at first, then halfway through I got inexplicably bored (probably around the time the cliché scientist released his cliché experiments). Crytek games are like Serious Sam games to me - I can't get involved with a tech demo.
HL2 got praised for more than the engine and how good the graphics were or weren't, and rightly so. I'd rather play Deus Ex 1 with graphics that look like arse than Halo 4 with spandangly effects, any day of the week.