This statement is made frequently, but when I've looked at data a few times it always shows that BYU's injury level is not statistically different from other teams, controlling for # of games, # of games vs. P5 or G5, etc. etc.  I haven't gone beyone a cursory look at the data, but what I did was pull weekly injury reports (from betting sites) for all FBS teams over the course of a season and then ran some very simple statistical tests to see if BYU was outside the norm of what you would expect.  I only did it for one season (I think it was back in 2017 during a similar thread on CB), but there was nothing there that indicated there was any meaningful to the hypothesis.

I know it's popular to use the S&C program and coaching approaches as punching bags to vent frustrations about win/loss record that isn't perfect, but football is a sport with a high injury risk and players will get injured.

It may be more apparent at BYU that an injury exists than at Alabama or Ohio State, due to the depth that those teams have.  The loss of a front line player at BYU has a disproportionate impact on win/loss outcomes relative to a powerhouse program, but it doesn't mean that there are actually more injuries.