Of course it is. Campaign donations are limited from many actors, you can't show boobies on TV, you can't swear on most TV stations, you can't disseminate information about somebody's personal life (in some circumstances).
And very recently in the US you could not speak out in favor of foreign governments in time of war, you could not disseminate books with certain sexual material, etc etc.
You can't disseminate false information about others that is harmful, you can't shout in somebody's face over and over and over (in most cases).
These are all regulations.
Besides you seem to have conceded that commercial speech is regulable. This by itself proves my point that we pick and choose what is protected by rights and to what degree the protected stuff is permitted or denied.