I was like that for quite some time (first resisting a mobile phone at all, later resisting a smartphone) - I was not the slightest bit interested. Then one day travelling somewhere with my son who had an iPhone 4, various things happened that opened my eyes to what it is and what it can do: it’s not a phone, but an amazing pocket computer with very cheap and free “apps”. Suddenly I could see the use, and for the first time started thinking maybe it is time to reconsider. Then said son upgraded his phone - and gave me his cast-off (first of several such occasions!)
Now wherever I am I always have access to a calculator, notepad, memo taker, diary (with event reminder), magnifier, torch, maps with GPS and personal location finder, compass, altimeter, language translator (multiple languages), cycling or walking route distance/elevation/speed tracker, satnav (I’d never buy for the car, but having available in event of having to find somewhere very awkward to a deadline it proved its zero-cost app worth!), portable music player capable of storing 100s of albums, book reader capable of storing dozens of books, remote control for my ‘proper’ camera including showing viewfinder image… Also various tools like sound level meter, light meter (both only approximate as uncalibrated), alarm clock, stopwatch, snapshot camera.
If I’m somewhere with wifi (I use PAYG without mobile data) I can access emails and browse the internet, access this forum, view satellite & aerial imagery, get news, get traffic and related information, get weather forecasts, view rain satellite tracking and nearby lightning, track aircraft flights, find a nearby restaurant, control my home music streamer, bank security device, etc etc.
Oh, it can also make phone calls. Very usefully that includes (when on wifi) free video calls worldwide - great for keeping in contact with friends and family in far-off places, and can send/receive short instant messages - and so much easier than in the days of rapidly stabbing each 0-9 key several times to type each character: how I hated that, so only used when absolutely ni alternative.
I don’t centre my life on it as some (young) people seem to do, but it is an exceedingly useful miniature gadget!
Mind you, out of principle I would strongly resist anyone demanding that I have to put something on my phone as described by the OP.
In terms of plain telephone calls, I’ve never been a bug user: I guess I make an average of only 3 or 4 calls a month - and that couple of calls a month - and that was the same when I had a mobile pre-smartphone.