Yes, about how to move it to another phone, especially when my current phone just died. Maybe I dropped it and now the display no longer works.
Oh, you do? It's still a single point of failure. Customer support servers down? Should have gotten a physical SIM.
Unbeatable servers? Good luck swapping eSIMs when you want to sell/throw away your phone abroad, out of range of internet. Should have gotten a phyical one.
Never out of range? Wonder what you do when your phone breaks and you have no one to babysit you through the process. Should have gotten physical.
Etc.
That's what an additional sigle point of failure means: less control over your own infrastructure.
New technologies often improve things in some way while introducing concerns and potential drawbacks in other ways. The question is whether, on balance, the new way is worth the risk.
My experience so far is that it is — it’s very convenient to be able to use a service like Airalo to order prepaid eSIMs for data service in foreign countries in advance. It makes traveling a joy now, and my wife is irritated a whole lot less by the prepaid SIM hunt I used to go on when traveling abroad. Plus no more tools or risking losing your SIM tray (or the SIM itself) when you swap it out on an airplane tray table.
My experience says that it will get steamrolled and the 1% left hanging, looking at significantly worse solutions, or none altogether.
I know we all hate telcos and mobile phone carriers -- and a lot of their mistrust is quite frankly deserved -- but this seems like an edge case that most customers won't even run into. First they need to switch devices, which eliminates most customers, and then second, they need to experience some kind of failure on switch. If the failure rate is any higher than before, I would be surprised. But let's wait to see the data before we all go up in arms.