if you dont grow more from 12 sets compared to 6 sets. then 6 is better.
if you cant recover from 6 days a week then training less than 6 days a week is better.
more isnt better, less isnt better. progress is best.
but since a lot is leading to that for HYPERTROPHY you need a lot of sets, more sets SEEMS to be better. more sets is better, at least it's not too few.
and if you dont go to failure, you can recover from 6 days a week. which means it's better.
more doesnt rule out progress. in fact more might be necessary for progress or at least speed up progress.