I pray for the rise of esims! I feel like it's on the cards.
You still need your phone and cell signal to receive them (at least many European carriers don't support SMS over VoWIFI); the eSIM is "stuck" in your phone if it physically breaks (and on many carriers, you can't re-use an eSIM QR activation code in any case); in many countries, SIMs expire after a couple of months or even weeks of inactivity, losing your number permanently, to name just a few.
I've found Google Voice to work quite well as a workaround for almost all of these problems, but unfortunately, many US companies insist on not allowing VoIP numbers for 2FA or even plain account creation purposes. I usually try to avoid these companies.
Wait, does this happen?
Your phone breaks (broken screen, swollen battery, whatever).
With a physical SIM you can physically extract the SIM and insert it in another (spare) phone (and you can even borrow one for a few minutes).
To transfer an e-SIM you need to authorize the transfer on the old phone (the one that doesn't work):
But in many cases, they either charge for it, require more or less involved bureaucratic acrobatics (including sending the QR code via physical mail as proof-of-address, because they've been burned badly by eSIM swapping), or both.
So the assumption that an eSIM activation (QR) code is more or less like a bearer token that you can keep in your password safe and use whenever required often does not hold true, especially when needed most (traveling internationally etc).
Fortunately, my provider is pretty good about it (I can instantly self-serve reissue an eSIM in their portal free of charge), but that seems to be the exception, and I also don't know how I feel about that, security-wise. (They don't offer 2FA, as far as I know.)
