Interesting.....
One wonders is it because they have no new product? Their new engines aren't ready? They don't want to listen to all the *****in about CAT getting out of the game (PACCAR was the big CAT user after all).
I do agree MATS isn't the big selling show it used to be. Manufacturers can't afford to wait for MATS to introduce new product and marketing is so much different than it used to be. But MATS is one of those things that you just do as an OE, your absence speaks loudly.
Speculation of course.