I don't *always* agree with Coach, (Like when he calls Utah dumb and boring and mediocre. 😏) but he's certainly credible when it comes to D1 football. And from everything I've heard, he's right about this. Players who use banned substances are the rare exception, not the rule.
I once heard Tom Hackett (2-time Ray Guy Award winning punter, Utah) talk about the testing.
1. The coaches were VERY explicit, about avoiding any banned substance, or even getting close to the line. The coaches also monitored the players very closely.
2. The team actually provided the players with approved supplements, protein powders, energy drinks, etc- at practices, training sessions, and before games, so that the players wouldn't take their own, and accidentally take something illegal.
3. Hackett said that he once took a stimulant capsule that he bought at a gas station, at practice. And Whit saw him, and questioned him about it, and then proceeded to chew him out for an extended period of time- and said something like "Well, Tom, I sure hope that you're not tested this week. Because who knows what's in your gas station pills?" (Whit knew it was fine, but he still busted Hackett's chops, because he didn't want his players taking anything not given to them by the program.) Apparently, Hackett was fine, but he said that the testing was still regular and random enough for him to be worried that it could be that week.
Then there's these guys:
https://www.thestate.com/sports/college/acc/clemson-university/article223720980.html
And there was also Will Grier- QB at Florida.
If the starting QB at one of the biggest programs in college football can't cheat the system- I doubt most players can.