Personally, because it's a useful metric to try to gauge system performance from, and since we still know almost nothing about what the next gen systems are really capable of, I care way more about that right now than how any one game in particular looks.
So if I see Returnal's graphics and think, well they're not mindblowing, but still a decent upgrade, then I'm gonna attempt to contextualize that information by looking at frame rate and resolution. That will tell me a bit about whether I should expect more or less or roughly the same from upcoming titles.
So in this case I'm looking for data that will reassure me that while this isn't a generational leap, that's only cos frame rate is x and resolution is y, and that as long as those factors are optimised in other games I'm still gonna get my lovely mindblowing next gen graphics.
Only, in this case, it's the reverse. So that's disappointing. Of course, it would be much more disappointing if we hadn't just seen absolutely staggering results from Ratchet in the demo last night. So I'm trying to just put it down to Housemarque being new to this and some poor design decisions.