Other than your carrier give it for free or cheap, I don't really see the reason why should you buy new phone. I've been using Redmi Note 9 for past 3 years and recently got my had on Poco F5. I don't see the point of my 'upgrade'. I sold it and come back to my Note 9.
Gaming? Most of them are p2w or microtransaction garbage or just gimped version of its PC/Console counterpart. I mean, $400 still get you PS4, TV and Switch if you don't mind buying used. At least here where I live.
Storage? Dude, newer phone wont even let you have SD Card.
Features? Well, all I see is newer phones take more features than it adds. Headphone jack, more ads, and repairability are to name a few.
Battery? Just replace them. However, my Note 9 still get through day with one 80% charge in the dawn. Which takes 1 hour.
I am genuinely curious why newer phone always selling like hot cakes. Since there's virtually no difference between 4gb of RAM and 12gb of RAM, or 12mp camera and 100mp camera on phone.
Simple answer: There isn't much of a point these days. Phones are quite capable to run for years. The big hurdle has been security updates, with OEM's cutting off models soon after launch.
For comparison, the Fairphone3 has received security updates for 7 years and the OS has been updated from 9 at launch to 13 currently.
Still rocking my galaxy s9+. It's starting to show its age and I've been tempted as of late to get an new phone, it's been 3 1/2 years now. I occasionally look for reasons like, oh it's running a bit slow or the fingerprint sensor is slowly dying.
My wife and I do put away $25/month aside to buy a phone every 3 years but eh. I just keep using this until it dies.
Makes more sense back in the early days, yearly improvements were actually noticeable. Things have settled down (ha jokes on your OnePlus) a lot, and getting a new phone yearly or every 2 years is less exciting now.
I look at it like buying anything else, over the "years".
And phones sometimes last me more than a few years, sometimes I just buy another phone because it's a hobby of mine and I like tinkering?
I'm also not tied to a carrier plan and have been PAYG for waaaay over a decade and half now which I suppose helps me budget better for when I do want a new shiny toy.
It really depends on your usage. My previous phone lived and was used for a good 6 years before it started acting slow, the GPS module acting up, and the battery puffed up.
It didn't make sense financially to pour money into to and fix it. Made sense to just go and buy one.
I just try to hop on trade-in deals to save money on upgrades.
Also for the battery, I have no desire to replace it myself. And paying for somelse isn't that cheap. If it was easy like the Fairphone then I would do it.
I live in the EU and here people don't often upgrade phones. This might be a US thing.
If I were to guess it's the average user who upgrades all the time because the carrier offers it and after 2 years they are bored with the phone. Some also think that tech gets old and must be updated often.
Tech enthusiasts know it's not true but the average user has no idea. Plus there are iPhone users who just want the status of having the latest phone.