A few studies have shown that the parallel squat is king for maximizing work and overloading on the muscles . High reps with low to moderate weight gives exercisers the least effective way to overload the lower body muscles. The deep squat can contribute to tight knee joints / kneecap pressure . With this in mind , would you put deep squats in your personal leg workout ?
I don’t think squats past 90 degrees of knee flexion, especially if the knees proceed anterior to the toes, are inappropriate for anyone (both genders) who isn’t a competitive power lifter. The post-patellar pressure generated during knee flexion past 90 degrees, especially under resistance overload, is dramatic, potentially leading to significant articular degeneration over time.
If properly progressed to, maybe. Progressions? Did that many of the people getting certified skip the part on progressions/regressions? Never have a client attempt an exercise that they haven’t demonstrate competence in performing the exercise at the progression level below that exercise level. EVER!