I'm more surprised that people aren't entirely on eSIMs yet.
People need to buy new phones for that.
I just got a new phone a few months ago. before that my phone didn`t support eSIM. This is the situation of many people, specially in emerging countries where phones are more expensive.
And my new phone has literally just one new feature, which is the eSIM. I wouldn`t have changed it, but my old phone felt and the screen broke