Unless my understanding of physics is all wrong (which is quite possible...), I'd think a locked breech .380 would be far superior to a blowback design as far as limp-wristing goes.
I agree with WardenWolf. A Browning locked-breech pistol is more prone to limpwrist.
The recoil is initially all put into the barrel + slide. The bullet has already left the barrel at this point. There's a little gas left, but most of the momentum has been transferred at this point.
Next, the barrel slams into the locking block. If there's nothing holding the gun, the entire frame will be knocked backwards by the barrel.
In a blowback pistol, there's no locking block. Only the spring transfers energy to the frame. The barrel being fixed to the frame adds its mass TO the frame, rather than working against it.
But I disagree on the P-64. IMHO, it has an inherently unreliable design. This is a great gun for a collector or a plinker, but not for carry. Out of maybe 50 rounds to date, I've already had a very curious light strike. Examination of the round showed a very light mark, perfectly centered on the primer. The gun has the strong stock main spring and a crazy 27 lb trigger pull, so this is just ***?? I've also broken 2 trigger return springs which puts the gun completely out of commission; albeit, one was a homemade replacement. If you look at the P64 forums, there are more than a few posted issues, including multiple modes of failure to fire. Some of these issues have no satisfactory resolution. Zero parts availability is a compounding factor. And then there's this:
The trigger pull is horrible, very heavy and extremely long,
which sums up the P64 trigger pretty well. I'd also add that it has a generous helping of over-travel and the reset is fairly horrendous.