A person is born with the inherent ability to communicate, unless they are mute, or deficient of the capacity. A firearm is a tangible extension of the individual, speech is not. The ability to make speech is not comparable to the ability to--well, the ability to make speech is comparable to the ability to make a firearm; but we aren't talking about that; and the former is more common than the latter.
The act of OC is a First Amendment exercise, IMO, not a 'keep and bear arms" exercise. But the acquisition of the firearm is a Second Amendment exercise.
The two are exclusive.