Yes, they are capable... probably not ideal.. they certainly can get the job done at a light level.
What you risk is: if you flip a rock while on a trail, it is more likely to hit the rim, versus a fatter rubber sidewall, which it coukd bounce off of.
You will also feel every single divot in that light dirt trail, especially the slower you drive. The suspension, being a truck, is stiff the slower you drive. So any little tiny dip, you're gonna feel it. Versus a fatter sidewall, like what 18s or 17s give you, where the rubber absorbs a lot more.
With 22s, there is also less room for airing down your tires... which often helps with traction, both light duty and heavy duty trails. Airing down helps absorb bumps, but with the low profiles, doing so may absorb a LITTLE more bumps and a LITTLe more traction, at the vost of the 22 wheels being more exposed.
As far as mudding goes, depending on just how deep your talking about, if you only have 4 inches of mud, or 3, you're probably
...okay. Fatter sidewalls allow you more, obviously, due to more depth before alloy.
I dont want to discourage you from enjoying the woods...everyone should... but helping to advise of the risks and sacrifices involved.