If someone needs CPR, all that goes out the window. If someone has watched a tiktok vid that gives them the basic knowledge to say 'this guy's not breathing. I'm going to try to help him,' any policy that says 'no' is idiotic. CPR is so ineffective already, worrying about how recently trained people are is a gross distortion of priorities. If they need CPR, it'd be nigh impossible to make their day worse. Same goes for worrying about the trauma of performing CPR where it doesn't actually save the person, which is the vast majority of cases. It's going to be traumatic no matter what if your coworker is dying, but the idea that you're going to prioritize the possible emotional trauma of the basically healthy individual over the literal life and death situation of their coworker is a wild way to triage that scene.

It's all just liability dodging. If only the managers/safety people are supposed to do it, the company can't be sued for 'letting' untrained personnel help. If the policy says 'don't help' the company can't be held liable for the workplace mental injury of the trauma of helping. Telling people who aren't helping to keep the area clear is sensible, though.