No, it appears that it is not.
Here we see an expanded .44 Special solid copper alloy DPX bullet from Corbon. It was fired into water. Note that none of the "new technology" handgun bullets are soft points but continue to be based on the jacketed hollow point.
While JSP rounds expand or deform in some mediums like ductseal or clay, when fired into animals I've personally shot or seen shot with them, it appears that they act just like ball. Apparently, most handgun velocities in the 800 to 1200 ft/sec range just are not enough to cause reliable deformation of jacketed soft points. (This most definitely is not the case with the myriad of "tweaked" jacketed hollow points now on the market; they normally work both well and consistently at realistic velocities for caliber.)I've not seen a human that has been hit with jacketed soft points that I can recall. The folks who study terminal ballistics and "stopping power" seem to pretty well agree that the JSP ammo does NOT expand reliably in tissue. Oddly enough, there are some soft points in rifle cartridges that seem to expand better than the hollow point designs, but such does not appear to be the case in most handgun cartridges.
It appears then that if we want maximum tissue damage and penetration we need to go with a quality JHP. If we seek deeper penetration, some sort of solid is called for. That may wind up being a SWC, WC or simply FMJ round nose. Unless reliability is an issue, I'd go with either SWC, WC or a flat-nosed bullet having a large meplat before going with the old round nose. While some opine that the shape of non-expanding bullets plays no role in "stopping" that which is shot, I've just not seen it. Round-nosed bullets have generally performed at the bottom of the pile in my experience. Those hunting larger animals with handguns almost always use a hardcast SWC or flatnose with a very healthy "flat" or meplat.
If a JSP is to help any at all in this regard, I suspect it might be because of its flatnose shape rather than its expansion characteristics...which are probably nil.