As the tired old analogy that free speech doesn’t give one the right to shout ‘fire!’ in a crowded theater means that free speech can be regulated, that regulation cannot include licensing tongues, arrest for speaking (at all) without a permit, limiting amplification capabilities (not use, just capability) of PA systems, arrest for unlicensed possession (not use, just possession) of concealable communication devices, etc.
Likewise, the manner in which the 2ndA may be Constitutionally regulated is limited to unjustified threatening, risk, or harm done, and equipment or usage which has undue inherent risk (may explode and harm user, unapproved possession in prisons, firing may ignite & destroy chemical/munitions factory, etc.).
Only argument favoring CCW licensing is at time of enumeration of 2ndA, concealed possession was considered presumptive evidence of ill intent; either impose minimal “good guy” licensing requirements, or reverse intense social opposition to allowing unlicensed open carry.
It is not up to govenment or the courts to change social perceptions, but the Supreme Court in Heller did specifically lay the questions of if, when, and how for concealed weapons at the doorstep of the individual States.
Which brings us back to the subject of this thread, Congress making general laws to observe CCW reciprocity as part of full faith and credit.