Use what you need, it's a tool.
Many of the pictures on here wouldn't be here if people didn't take their phones, they're often better than just snapshots. The tech in the lenses and sensors is quite something.
I have a DSLR too, but it is big an bulky, but fun in its own way. Not something you want if you're riding or popping to some place for a general visit. It brings memories easily for some.
If you don't want to use it, don't use the camera.
I use it to pay all the time, don't carry cash and places miss out if they are cash only, their choice.
I'm replying here with it now, outside in the garden relaxing.
People with heads in their phone, I sometimes do it but then it's only a newspaper or book replacement. (or map).
Can take notes and look thing up really easily.
Get one, they don't cost a lot outright for something in the middle with NFC (for payments).
You don't really need a SIM/4G if your happy to use WiFi if available. I did that for many a years, had pay as you go and just topped up if I was going somewhere I needed the data.
But using your phone at concerts etc, yep I agree with you, why?
For a few seconds so you get that memory that shows up in a few years and starts a conversation, yes, but for minutes on end....