[tstrimple]

Is this because of an older version of iOS or specifically because of the shitty carrier? I can add and remove esims from my iPhone. I just recently added one for my new 17 Pro Max. It prompted me to login to Verizon and it "just worked". There is an option right there to delete the Verizon esim. Nothing restricted or difficult about it.

[lagadu]

Try doing it without any sort of data connection, where the phone can't ask the carrier to deprovision the esim.