From my very limited experience, I get the impression that traditionalists tend to think that they know better than respected authorities on a lot of things. They think they know better than the church in regards to the liturgy. They think they know better than the vast majority of scientists in regards to evolution (and sometimes geocentrism). They think they know better than highly educated medical doctors and get involved in alternative medicine and things of that sort.
This isn’t to say that authority is always right and should not be questioned. Sometimes the authorities are wrong. However, I think that questioning valid authorities sometimes gets carried to an extreme by traditionalists, resulting in things like the SSPX, geocentrism and alternative medicine.
I think that this phenomenom also carries over to evolution in many respects. Most traditionalists have no scientific training or experience, and are not in a position to evaluate evolution. Still, many oppose it despite this limitation. Ultimately, evolution doesn’t matter in regards to salvation. I think some opposition to this mostly theologically irrelevant theory comes from the desire of traditionalists to know things better than the rest of the world.
Perhaps this attitude of “knowing better than everyone else” could easily lead to a form of gnosticism.