There's a lot of cool-aid in this thread.
As I have said in the past...S&W can call the darn thing a squirrel and it is still a slide stop and a slide release. It is even serrated on the top to assist in pushing down. It is located in the same spot, and functions in exactly the same manner as slide releases have since the 1911 and before.
The use of the slide stop/slide release/squirrel button will not wear out any more than any other semi-automatic pistol. I can say this having put well over 50,000 rounds through various M&Ps, working with fellow instructors who have fired similar, if not higher number of rounds, and training hundreds of recruits and in-service personnel. My department is in the process of a conversion of potentially over 9,000 deputies. We were never told not to use the slide-stop/release/squirrel button as a slide release.
Use extreme caution taking advice, let alone Gospel from the internet.
For those M&Ps that have exceptionally hard-to-release slide stop/release/squirrel buttons, we simply tell the deputy to practice with it for a while and it eventually works in...If they want to use it as opposed to the overhand rack/power-stroke.