Many sighted players don’t need to look at the frets either. There are also fretless stringed instruments like bass, violin and cello.

I don’t play, but I have known many blind guitarists. Is there a reason you think they can’t feel the strings and frets?

I'm only visually impaired and am able to see frets. I'm not really a guitar players (I tried to pick it up once but my fingers don't have the agility for it I guess). I can image a fully blind starting guitarist could feel the frets and then locate a certain one by starting at the nut and counting the bumps they encounter. This is especially true on acoustic guitars. I think that over time guitarists develop some sort of muscle memory where they can move a certain number of frets up and down the neck subconciously without looking or thinking about it. I've known great blind cellists so I'm pretty sure that it's not really a problem, although many kudos to you for considering the blind community!
One think that could be a great quality of life improvement for blind guitarists would be a talking tuner device I imagine. There are alternatives but tuners are nice and accurate every time, even in noisy environments.

There is a guitarist saying that “tone is in your fingers “. This means that your years of skill and practice are far more important than the instrument which you are playing. I am not blind, nor do I play the guitar, but none of the guitarists that I know look at their fretboard once they are past the beginner stage.