A UTV is lighter. UTV has 4 wheel lock and mini trucks have differentials that are open. Would be like comparing a WW2 jeep to a side x side. But I worked at Polaris and saw them leave out with a cab and doors for $46,000.00 all day long.
I work at a farm a good bit. They have a Honda pioneer, quit and pulled to the side. A 2021 Polaris, quit and pulled to the side. I've been rolling over that whole place in a $500.00 Expedition for a few years now. Good glass and interior, no dents, cold AC and warm heat. Loaded with tools. Hit 200,000 miles last year. Ain't spent a dime on it other than gas and a little oil now and then. Never changed the oil.
For what I do, a mini truck would be just fine. How are they in the mud? Well, if you even need to ask that, probably should get a UTV. I don't play in the mud. I avoid mud if possible. We might get stuck now and then, but its pulling a16' disc, or an 8' offset disc, and the offset one is the worse of the two. We usually keep the big 4x4 tractor free if there is any question about things. We also have a log skidder with a winch but have never used it to pull a tractor out.
We also have a side x side. It's handy. But when you lock both ends up, I can't see a mini truck hanging with that in any shape, form, or fashion. We only used the true 4x4 when first purchased. When it's cold and drizzly bone chilling, you may prefer a cab with creature comforts. So I guess, think of what all you'll be doing with it, and decide what's best for you. I have seen mini trucks with ATV tires on all 4 corners and those guys kept them trucks and still have them. A crew cab mini with 4x4 and a tow bar would be the bomb for me.