My battery lasts 2 days. If I'm away for a night I pack a charger along with my toothbrush and clothes. I genuinely cannot remember the last time I was caught off guard by this.
> Or lose the phone?
Short term - same as if I lose my keys or my wallet. It's a giant pain in the ass. longer term, doesn't matter, new phone + restore from backup. I don't need to phone my bank and cancel my cards, or change the locks on my doors in case my keys were pickpocketed and I'm targeted.
> Or it gets wet and won't turn on?
Many smartphones have been ip68 rated for the best part of a decade. Note that to not turn on, you're realistically talking about submerging it, not just being out in the rain. Maybe I live a more sheltered life than you, but finding myself unexpectedly submerged is about as extreme a situation as I'm going to find myself in, and not one I plan for other than being able to swim.
Fwiw, my 2022 IP67-rated Samsung phone failed after a few mild water splashes recently. It's supposed to be resistant to 1m submersion for 30 minutes, but failed with much less water exposure.
I was stuck without essential functions until I could get it repaired or replaced. Luckily I was able to get it opened, cleaned and dried and a new screen fitted by a local repair shop within 2 days.
Without my phone, I can't pay things on my credit card sometimes (some payments require phone app 2FA), and I can't login to several of my bank accounts (they use authentication by mobile app even for web-based banking on my laptop).
It doesn't really run out of batteries. I'm not talking about going to the moon, I'm talking about going across town. It charges pretty quick, and it can charge in the car, so I'm rarely out and about with it less than 50% charged. Which is good enough for at least 8 hours of active usage with its current battery health and age, a good bit more if I bother stretching it.
What happens if I lose my wallet? What happens if I lose my car keys? Its not like these other things are immune to "what if it gets lost?" Sure, there's a bit of risk tying it all to one thing, but in the end I'm not talking about being more than a few hours walk to home or a friend's house. And like I said, I usually carry enough cash in my shoe to cover a half day fare.
At least for my car, I do have a backup code I can type in and access it.
My phone is waterproof. Its durable enough, its fallen out of my pocket while riding my bike before and been fine. I did have a problem of breaking phones in the past, but since waterproof phones and far more durable screens have been a thing I haven't really lost any to damage since. The last time I broke a phone was 2012. It seems like if I managed to break my phone I'm likely to be picked up by an ambulance anyways.
You can't even drive your car?
My phones have failed me on multiple occasions over the years.