I suppose for me Apple Watch comes in handy too - it's like double protection. I don't have car that can use the key but if both your watch and your phone can do it with UWB that's at least double the resliance of just having a key would usually be.This is exactly what I do on vacations.
This is a bigger concern than losing phone and not having the key with you for the car.
If that happens, you can just take an uber home and get your fob. If I was going out of town, I’d definitely take my fob ; but for short trips near home having this feature would be great.
I do have an EV though and there's been a couple of times in 8 years where it's been handy to have an app to unlock it. I remember in the past many times people locking their key in their own car. In fact that happened to me once around 2009 - I shut it in the boot (trunk) and roadside assistance had to come out with a magnet on a long pole. Thankfully those mistakes can't be made so easily anymore!