The dictionary supplies two definitions of regulated:
regulated: past participle, past tense of reg·u·late (Verb) Verb: 1) Control or maintain the rate or speed of (a machine or process) so that it operates properly. 2) Control or supervise (something, esp. a company or business activity) by means of rules and regulations.Definition 1 was what was intended, not 2.
The Regular Army is called that because they are trained to be well regulated (definition 1)
You are correct and bring up a very important point - one that is almost universally ignored, purposely obfuscated or misunderstood. "Regulate", in the language of the Constitution, is most accurately understood as "regularize" or "standardize", not as intending control, restriction, limitation or infringement. This applies both to 2A as well as the Commerce Clause.