Tim, the Sights are visible/usable as they are higher than the top of the rail. This was by design by Mossberg for sight usage without optics. Cheers and stay safe!

Tim, the rail will not be in the way to see thru the iron sights. Have a great day!

You can see through the sights with the rail on. But most optics are going to block your view unless you used a low mounted pistol reddot like an RMR.
Good picture of the sights here (the picture is of the 300 blackout version, but the sights are the same for 308 version too.)
thefirearmblog.com/blog/2021/09/09/mossberg-300blk-mvp-patrol/