Some old wands can dig into the carpet on the forward stroke, but by working against the grain or across the grain this can be reduced, also get them to lower their hands on the forward stroke.
In other words.............check that the best technique is being used. I've seen people " fight the grain " over the years and all they get is a lot of unnecessary pain.
Never used glides although I made up DIY plastic lips many years ago to make it easier to deal with a big hotel job. Long before glides were invented.