> The major advantage is now that the expensive and time-consuming part ... is ... sending out a physical SIM card

For the carriers I can see that. Especially the part where users can't move their esim without carrier cooperation. That grants telcos (and sometimes handset manufacturers) additional control over users - control that they don't get with physical sim.

And physical sim save me time and money. I get a new SIM each month. It's 1 min to swap it and update my forwarding #. Service is reliably cheap.

When I need my sim elsewhere (ex:5g router), I just move it.