Utter nonsense. There's no technical requirement to get a new QR code, this is up to the carrier.
Why are there so many people spreading straight up lies in this thread?
When I wanted to move to a new phone, I simply deleted the data profile from my old phone and scanned the QR code on the new one, as the provider suggested. It just worked.
Some commenters here are correctly saying that the carrier could technically prevent physical SIMs from being moved between phones by restricting which IMEIs are connecting to the network, but that's not usually done and there's an established convention that SIM cards can be moved around. eSIM gives them a blank slate to start over and break that convention without much backlash.