Ummmm....I think he is referring to campus carry which is not legal.
Please elaborate on your statement that it is perfectly legal.
The OP asked about carry in one's car and
Phoenix mentioned "securely enclosed in the car" (it's actually securely encased) so I assumed he meant he cannot keep a firearm
securely encased in his car on university/college campus.
790.115(2)(a) generally prohibits carry of firearms on school property (including college/university), however it also has an exception that states (paraphrased): "a person may carry a firearm in a vehicle pursuant to s. 790.25(5)"
And the other relevant statute, 790.06(12), indicates the CWFL does not authorize one to carry into "any college or university facility", but a parking lot is not a facility.
So 790.06(12) does not apply and 790.115(2)(a)(3) specifically permits it.