I was a competitive swimmer in high school. We had practice twice a day, and would always get pissed whenever we got a paper cut.
Because we never let the cut fully dry out and have a scab form, small cuts would take MONTHS to heal, and often result in scars when they shouldn't have.
Because of that I always assumed, dry conditions were ideal for healing.
New tissue growth is like the rest of our biology. Proteins are made in water solution inside cells. That has to get to the new tissue. Providing a scaffolding with a warm, wet, nutrient-rich environment around the wound should in theory make it heal faster and with less scarring, too. But these environments are also good for pathogen growth and invite infection. And removing detritus and pus and nutrient/gas exchange become issues as well. So just how moist and packed to keep a wound, and with what kind of packing and moisture, has been debated back and forth basically forever.
I see hydrocolloid bandages in pharmacies/groceries a lot nowadays, so hopefully they’re helping modern swimmers avoid the pain you went through!