Yep, and there's a good reason. Kicking puts you at risk of getting take down and it's bound to happen with one of your kicks. So they naturally have to learn to work well from their back. Wrestlers don't like being on their back and boxing is less risk. Boxing and wrestling also have a very forward aggressive stance so punches set up shots very well and the threat of takedowns set up boxing combos. Kickboxing and wrestling don't have the same chemistry as a kickboxing stance is much taller and kicks don't set up wrestling techniques.

A lot of new mma fighters only go into an mma gym and learn what those gyms teach them. Most of what they learn is Boxing, Kickboxing, and wrestlnig or Jiujitsu.

A lot of fighters are different and some of these new ones are learning more than what they learned in MMA and are having a LOT of success now.

What Jacob said. (Too fresh here, so can't vote his answer up. But the tactical aspects he touched upon are pretty much it.)

i find both striking guys and jit guys find it hard to transition to american wrestling

but not the others u said to a lesser extent

I find it kind of peculiar that kickboxers tend to be more Jiu-Jitsu oriented in their grappling/ground game and vice versa; Jiu-Jitsu guys tend to favor kickboxing. Examples of these types of fighters include Carlos Condit, Jose Aldo, Anthony Pettis, Donald Cerrone, etc. Wrestlers tend to be more boxing-centered when it comes to stand-up fighting and vice versa. Examples include Eddie Alvarez, Frankie Edgar, Jake Ellenberger, Cain Valasquez, etc. I just really noticed that there aren't a whole lot of boxing/jiu-jitsu guys (ex. Nick Diaz) and there aren't a lot of wrestlers who excel at kickboxing (ex. Georges St. Pierre). They are just less common. Anyone else find this kind of funny and why is this the case? I do Muay Thai and Jiu-Jitsu myself and I just find that this is an interesting trend in MMA.