I have been shooting 9mm since about 1970 with Lugers, P38, Browning Hi Power, S&W gen 1-2-3, Glock, Kahr, Beretta 92, and probably a couple others that don't stand out in memory.

Bought my first .40S&W in about 2004, Kahr P40. 16.1 oz. empty weight, polymer frame, very light, compact. After a few hiccups during the first 100 rounds the Kahr settled in nicely as a reliable and accurate piece. Recoil in the lightweight pistol was noticeable; I would call it sharp, abrupt, very brisk, and a few other adjectives. Not a combination I would enjoy an all day range session with, but a good and reliable piece.

My more recent .40S&W (November 2018) is a Sig P229. Compact version of the P226 series, 12-round magazine, DA-SA-Decocker, alloy frame. Very good ergonomics and enough weight to take the recoil of service-grade 180-grain loads in stride. Also extremely accurate and completely reliable with everything I have fed into it.

Based on this limited comparison I would agree with the OP. There is little difference in felt recoil or recoil impulse when compared to 9mm pistols of similar weight (Browning Hi Power, S&W 5906, etc).

As an old 1911 .45 aficionado I am pretty well accustomed to pistols with some recoil, and I appreciate some weight to control that. Overall, I like the .40S&W quite well and recommend it for serious "social work".