Heyo as far as I know there are different advantages. The provider doesn’t need to send a sim card to the customer, so there is no production coast and no postage. This will reduce cost because of the amounts of cards. For the phone company it will reduce repair cost, because sometimes the SIM slots are damaged and won’t work probably and for the customer the advantage would be that he could get his eSIM data right when he has the phone connected to the internet.
But beeing forced to use eSIM is not a great deal. I am truly for a dual variant where the device is both SIM and eSIM enabled.