That "little switch" is called a slide stop. I've used it to release the slide on a first gen glock 17 since 1988, putting over 100K of ammo through it without having it damaged or need of being replaced.
Can it damage the slide stop using it to release the slide? You tell me based on what I just told you above. Opinions vary, but I don't know of anyone who has as many rounds through one glock than I do.
I've used the slide stop to release the slide to go to battery on all my glocks forever and a day. None have had to be replaced due to wear yet.