Well, that is fine. The university has every right to restrict what the professor can or can’t ban in his classroom. I just don’t agree with them that this would be the default situation, if the university took no position on the matter.
Obviously, the state law does not force universities to allow firearms in every part of campus under every circumstance. They still have the ability to institute bans of a less than campus-wide scope, so it stands to reason, absent any specific policy by the university prohibiting it, the professor would be able to institute such a ban in his classroom.
The University itself said the “Professor Peterson’s comments directly violates Colorado law.” I don’t know how much clearer I can make it.