Did we watch the same video?
There was nothing in there about any advantages to the PX4 magazine except that it is engineered atound .40SW, which in 2023 is no longer an advantage.
Everyones concealment needs are different, but I know for me, carrying AIWB, the width seems to be the single biggest factor, perhaps tied with the shape of the heel.
I would not want a thinner slide, the PX4 slide is already a nice width for mounting dots.