My observation over the years has been that (1) most folks I know who possess CPLs (or CHLs/CWLs/CWPs/CCW licenses, whatever they're called in your state) DO NOT actually carry a firearm on a REGULAR basis; and (2) that most folks who actually do carry on a regular basis already carry small guns, typically .380s, compact/sub-compact 9mms, J-frame .38s or even smaller, and that very, very few people are dedicated enough to carry full-size handguns.
So, no, I do not believe magazine capacity limits will cause more than a handful of folks to even think about going bigger in caliber, because I believe most folks that carry, already carry small handguns with small capacity.
Now, I'm sure many here (on this dedicated firearms forum) will jump up to contradict me, but seriously, guys, consider: what do most of the (non-law enforcement, non-dedicated gun-carrying) people you know REALLY carry? And I live in a state where open carry is pretty well-established, and our shall-issue concealed carry law is (arguably -- sorry, Indiana) the oldest in the nation.