RNFP is an old style that has made a comeback with the rising popularity of cowboy action shooting, which uses primarily revolvers. TCFP seeems to work better in finicky autos that have a problem with feeding SWCs. I don't know if there is any real difference between the two feeding in autos, because I've never tried RNFPs in them myself, I do know that TCFP are more "modern" which may or may not have anything to do with it.

You are correct that there would be little difference in a revolver as long as they both have the same meplat dimensions.

.40 S&W was made to be fit into 9mm frames sizes which leaves them with a longer case and a shorter OAL, leaving less room for a long nosed bullet.