For a lot of less technically inclined folks I think eSIMs would introduce a lot of complexity. Swapping a SIM card is rather straight forward, and I know that for example my mother could easily do it by herself and has done so in the past. I don't think she would be able to swap an eSIM using the customer portal of her operator if it was necessary. I could see this causing a lot of headache for customer support or nearby relatives ;)
Personally, I would also prefer to have the SIM-tray as a backup and for travel. Most prepaid plans in Europe still don't support eSIMs.