Heh basically people don't consider their overall equity at all. And flush draws on a board kill a bare hands equity.
In a nutshell people in live plo don't fold. I mean at all. You've got 7-10 way pots every hand.
Similar to nl, in a game where people don't fold, you need to have what will often be the winning hand at showdown. (again a simple concept people don't realize) This is why it is ok and correct to be tight ABC and bet loads with your value and to basically never bluff.
Back to plo, people greatly overvalue a hand like 7
9
T
J
on
8
6
4
They think they need any 5/7/9/T but what they actually need is a non
5/7/9/T which equates to 3+2+2+2 or 9 outs which isn't alot of outs in plo. Further complicating things, you are often getting freerolled by a similar hand with either a set, 2pr, hearts, or diamonds. So like 6
7
9
T
or 7889 or A
7
9
T
etc etc the list is huge obv and since every hand is ten ways people have your draws covered one way or another at all times.
This is where the real money is made in live plo, selecting hands appropriately preflop and overnutting people post.
Going back to nl, plo just really helps you think about these spots because you start truly thinking about turns in a much better way. For example in OPs hand an 8
6
4
flop would be much better because we have all the
turns that we can barrel. An 8
6
4
flop would be best because we have more fold equity (less draws call otf) more nut making turns/rivers, and again more turns we can barrel.