Cash out is great option to reduce variance, i'm using it from time to time especially when i have 80% equity like AA or KK vs small pocket pairs against one or two opponents, cause sometimes they will catch some flush draws/straight draws or hitting their set.
But sometimes with AK vs QQ or JJ i don't cash out cause it's a flip, i would prefer to take the risk and win full pot.
I play 10 PLO ZOOM exclusively these days for cash games, and I think that the strategy may be different in some ways than Hold'em.
I find that if my equity is really high in a heads-up situation, if I am in for 1 buy-in, I will let it run out. I will either end up with 2 buy-ins for my next hand or 0 buy-ins.
If I already have 3-4 buy-ins for a starting stack, I will probably look for a more chip protection strategy here. For example, let's say I'm all-in for $38, and I could either cash out for, say $70, or run it to win $82, but the RISK is if I lose, I'm down to $0, then I'm taking the insurance. Maybe that makes me somewhat risk averse, but in that situation, if I have a guaranteed big score locked up if I cash out, why not do it???
If I'm in a multi-way AIPF pot for one buy-in, with 30% equity (but everyone else is about equal), I'm going to run it out, because I'll either win 3+ buy-ins, or lose 1, the reward is much higher relative to my risk. Plus, in that situation, cashing out means you're going to be a net loss for that hand, so why even play the hand to begin with?
As for Hold'em, it's different for sure, and I don't know what to think about it, but in a coinflip situation (QQ vs. AK), I agree with the one person that said to run it out.