What exactly did eSIM enable here? With dual SIM phones, you can even put one data SIM and one number SIM in a single phone at the same time. Plus it's simple and easy to move either SIM to any other SIM-compatible device at any time.
Some examples include
* Backup service in the event that an attacker gains access to your Google Fi account. A backup eSIM with data service for a year has pricing starting at like $2.
* Fast network access in other countries. As far as I know, Google Fi is a carrier in the United States, and does not include network access in other countries.
* Deprioritized on data? The ability to instantly buy a major carrier eSIM and have the data speeds back.
Google Fi offers network access in over 200 countries.