I find graphics in games to be very similar to a mix of video quality and sfx in movies.
They can make WOW moments or build atmosphere, or draw you in more easily, and they tend to age rapidly.
However, usually I can adjust to older sfx or poorer image quality after a short time, and once adjusted it tends to become irrelevant.
(actually, you tend to get diminishing returns for the good stuff too).
For example, I watched a crappy low res version of A New Hope a few days back, and the beginning was a bit jarring and clunky in terms of both image quality and SFX. But 20-30 minutes in the movie had grabbed me and it became pretty irrelevant.
Then, when the new-but-aged CGI first popped up it was a bit jarring, but after a few times it became irrelevant again.
When I watched Avatar or other 3D movies, the first 20-30 minutes were mindblowing, but by the end the impact of the graphics and 3D had mostly passed.
Similarly, I was very late to move to DVD because I had hundreds of movies on VHS. And I was quite happy watching them on VHS. Once I did move to DVD, the impact was big, but quite limited in duration. Then when I went back to watch an old movie on VHS I was like “oh my god, this is horrible, how can i watch this?” and then 20 minutes in I was hooked on the movie and didn’t notice any more.
So, yeah, at the time Doom would suck me in and the graphics were stunning. Or at the time Jedi Knight would suck me in and the graphics were stunning.
Now, if I went back to them, the graphics haven’t changed, but they’d seem terrible… but if the game sucks me in then I’d cease to notice that after a while.
Clunky controls and gameplay however, I find a much bigger hurdle to adjust to.
So, yeah, graphics are good for first impressions, but aren’t much more than skin deep.