Definitely a good idea to plan on this at all times. In my case this looks like:

* All photos auto upload to Google photos

* All other important files are in a syncthing folder with at least two other devices (laptop+desktop)

* 2fa in Authy with cloud-sync

* Passwords on Firefox sync

* Google Fi is my carrier, and pulls eSIM when I log in to the app even without my old phone

* Google voice number is my main phone number. I don't lose access to incoming or outgoing sms or voice calls if I lose my phone.

In a pinch, I can buy a cheap prepaid phone and sim while traveling and be fully functional and reachable. I've had to do this before, and while I probably wouldn't go to the trouble for work, I feel compelled to be at least reachable for family.

I've thought about de-googling this further; photos could go straight into syncthing and I could port my # to a generic SIP provider that offers SMS. So far neither have seemed quite worth the trouble.

I've always felt very uncomfortable treating my phone as anything other than a rather overpowered thin-client.

Yes but I don't want my phone to be lost or destroyed or stolen. So using a phone that will likely fail until it does so is not taking preventative measures.

They are stronger possibilities once you know they are going to happen eventually, not just that they could theoretically happen.