I'm on US Mobile as well and I've never had any issues getting a new eSIM or using a pSIM. I've never used Visable though, so i can't commit on how GrapheneOS works with it.
Quick question though, as a fellow US Mobile user, do you use dark Star, and if you do, were you able to get RSC messages up and running? I had it working great on Light Speed, but when they came out with all the unlimited deals on dark Star I upgraded my plan and switched to dark Star, but I never got RCS to work since switching to Dark Star. I've tried just about everything. I'm seriously thinking about loading stock Android on my old pixel 8 to see if I can get it work without GrapheneOS, because I can't think of anything else to try.