Warlockmaker, the current trend seems to be towards Peritoneal Pull Through Vaginoplasty, where the lining of the tummy is used to line the vaginal cavity, commonly created as part of a 2 step process or revision. It produces a self lubricating cavity with almost identical properties to a cis cavity, including stable vaginal flora. It also apparently requires less dilation, which is a major attraction for many.
Multi step vaginoplasties can work out to be very expensive, and each step requires almost the same recovery time as a one step operation. Weighing all these up can help trans women decide what is best for them. My specialist nurse who does my post op care told me I had chosen shallow depth wisely, as she found that 60% of women over 55 (I'm 66) who get full depth, allow their cavity to close within 5 years. I am asexual, so there didn't seem to be a justification for full depth.
Just for interest, are you saying many younger women choose shallow depth because they want to avoid the extra surgery?
Hugs,
Allie