Recoil is a very subjective thing. I'd agree that recoil is generally similar with "WWB" style loads. The big difference, though, is that the 9mm is a more effective cartridge at even standard pressures... You have to go 38+P to get 9mm performance, IMO. And 38+P in the j-frame lightweights is much more stout than any 9mm, IMO, and takes some practice to shoot well. I bought a case (1000) of them, and practiced like mad... I now shoot my snubby quite well.
I carry Speer GDHP +P in both my M&P340 (135gr SB load) and my PM9 (124gr +P), and I find the PM9 a lot less in the recoil department. Save some rubbing at the base of my thumb, I can shoot my PM9 all day... Not my snub, even after I built up the proper callouses.
Really I think a PM9 with 124gr +P is a more effective load, with 2 more on tap, and easier to shoot accurately. You really can't go wrong there. But I still do keep/shoot my snub; it's a better option for pocket carry, IMO, and I use it whenever I'm going to an area I have to disarm (which is a lot of friggin places in Ohio), as it's safer to re-arm by slipping the gun/holster back into my pocket than trying to stuff a striker-fired semi in my pants while seated in a car.
So my snub still gets some use.