The eSIMs in phones are reprogrammable with new "profiles", and Android can store multiple profiles and reprogram the eSIM with whichever one you want to use. Non-programmable eSIMs are only used in embedded devices.
Android 13 also has something called eSIM MEP that allows it to do dual SIM using a single eSIM chip.
I use it when outside the EU, to get cheap data without having to swap SIM cards. There's a bunch of providers where you can sign up online (usually with an app) and then install the eSIM. Pretty happy with the process. Saves me the hassle from going to a shop and allows me to continue using my regular SIM for receiving calls and such.