One factor nobody's mentioned yet is the season of year.
If it's summer and the water temps are warmish to mild, I'mma dive in a wetsuit, so getting my person wet before or after the dive ain't a concern. Getting rained on may even make slithering into a wetsuit easier.
If it's winter and the water temps are chilly, I'mma dive in a drysuit, meaning I need to guarantee that I'll stay dry until I hit the water and at least have a strong chance of staying dry when I unzip. Wet underwear usually has a negative-insulation factor, y'know.
Agreed. Are you able to change into your undies and drysuit at home, or in your car? I haven't tried putting mine on in my car, but it seems doable. If neither are reasonable, maybe an easy-up is the way to go.