Comment by microtonal

Same here, KPN, NL. You have to install the KPN app on the new phone and log in. Then you request an eSIM on the new phone. You get an SMS auth code on the old phone. You fill the auth code on the new phone. Then you have to remove the eSIM from the old phone (with the new one not provisioned yet). Then confirm on the new phone and cross your fingers that provisioning works. Presumably (according to the docs) when it fails, you can reprovision the old phone again.

The process made me so anxious the last few times, that I went to the carrier shop and asked for a nano SIM. Now life is bliss again.

It seems that eSIM is primarily an advantage when you need to get a new SIM, but other than that I don't really see much of an advantage for me as a customer.