Does the 1 piece rail really make loading that difficult or is this an internet complaint?

ETA: Its a Rem 700 style rifle.

Does not bother my 700's,I always liked the stability of them.

I suppose it would depend on the rail & rifle.
I've seen some that have a scalloped out section to make less of a blockage to loading/ejecting.

My Tikka is mag fed, so I've never thought about it.

Can you get your fingers in to pull out a spent case that the extractor failed to grab? If you have a blind mag, how much of a pain is it to load rounds into the blind mag?