This is not an issue of procedure, generally speaking...
Whether one returns the slide to battery with the slide stop or pull&release is not the issue here.
It's the impact damage upon the slide stopping that's causing this and not how it is released.
Now, one may argue that given substandard components, the interaction upon stopping the slide may be aggravated by wear caused by using the slide stop to release the slide but, the underlying issue there is still component quality and not procedure.
This is first:
Slide metallurgy/preparation
Then potentially:
Slide stop
Mag follower
and/or:
Dimensional flaws
There IS something wrong here and it IS NOT the shooter. Regardless of esoteric "truisms".
Todd.