I also use PT4 and also am considered f***ing awful by it when it comes to those numbers. It seems to think you just shouldn't have a fold button, which is fine and all, except you'll allow low-stakes nits to print money. I don't know which sample of "winning players" it took to make those numbers, but they won't be good low-stakes regs that's for sure. I would consider having a fold% in the ranges it suggests for 6-max PLO to be pretty goddam terrible against most low-stakes lineups.

Edit: Just had a look at all my numbers for it and I very rarely fall nicely in the middle of green. It thinks I'm on the tighter side of okay, too aggressive, and fold too much postflop. So yeah, I wouldn't worry about it if you are consistently beating the games and feel comfortable in them.

Oh, it also suggests limping quite a few hands UTG which I think is pretty bad and wouldn't really be doing. It therefore likes to complain I've never 3-bet UTG which is funny.

I ran Leaktracker today and the suggested fold to F/T/R numbers also struck me as way off. It makes no sense, especially in conjunction with what the suggested fold to flop c-bet numbers are. 

Apparently this is a known problem though: https://www.pokertracker.com/forums/viewtopic.php?f=58&t=39281&p=197271&hilit=fold+to+leak+tracker#p197271

That thread may have been for NLHE, so it's possible they are not aware of the numbers being incorrect for PLO as well and therefore have not fixed it in the past year. It's a little surprising to me that they still haven't addressed this tbh.

Weird. Leakbuster from HEM seems pretty good , I thought it was practically the same. 

My stats are EXACTLY the same as yours. Everything normal in the leaktracker but I'm way out of range on those 3 stats.   I'm not even sure if those stats are referring to cbets or just  bets  ?  I basically disregarded them figuring they had to be off, but now that you've brought up the same thing hopefully I can verify that this is in fact just a bad stat check ?  I wonder if everyone is way out of range for these 3 in leaktracker ?

I don't have PT4 nor did I carefully read all of the responses above but here is something to consider:

It's possible that it's "good" range for % fold by street post flop is for games that are usually heads up post flop.

Or, more generally, in games where there are lots of players in on each street post flop you're going to have to be significantly tighter than one would otherwise.

When pots are heads up you have to protect yourself against exploitation (in theory) by defending a minimal amount.  When the pot is 4 ways and it goes bet then call or raise in front of you, you don't have to worry about keeping any opponents honest.  The number of players in the pot implicitly protects you from being bluffed so you don't have to have a bluff catching (nor a big bluffing range) anymore.