Yes. It's much easier for the masseuse without having to work around under garments.
In our parts the regulatory bodies that certify RMT's are very strict re: proper draping and 99.999% of RMTs would not jeopardize their license with inappropriate touching, which in reality could be done clothed, naked, draped or undraped. We had RMT massages in Sept at a fancy spa just to use up our annual benefits. The form I signed had a separate signature spot for me to acknowledge that I was ok with the RMT massaging my buttocks / glutes through the sheet that covered me. No signature would have made them a "no fly" zone.
IMO though semi clothed massages are like wearing your bathing suit in a hot tub...not doing either. LOL