Gregory's Server@joelle I cannot follow you. This study https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8099405/ suggests that selection criteria are useful because regrets are very low, 1%. And you said initially that the regrets in the wild west of breast augmentation is 20%. So this is already a proof that some regolumentation is beneficial.
We can discuss if the 20% of regrets are linked also to the low quality of some surgeon, and not only to patients not knowing really what they want. But, the difference is rather large.
@mzan The authors note that selection criteria have improved (I.E. gotten loser) for GAS. They didn't actually study that though, it's conjecture. They also didn't compare not having the psychological gatekeeping with having it (if they think the modern standards are better, then what about even loser ones? They don't know because they didn't study it).