I've been bi-annual since I got my first smartphone, but I'm going to make the leap from being an Android user to Apple user and I'm hoping to do 33-36 months between upgrades. Largely driven to the ecosystem leap by data privacy concerns and the relatively seamless hardware ecosystem of Apple, because I'm planning to do phone+smartwatch combo. That obviously means two devices to upgrade when it's upgrade time, so the extra time will give me a better budget. Would be nice if I could stretch 4 years, too, but I feel like I'm a little too consumer-engaged in the tech industry to resist the pull of beefed up hardware specs... But we'll see.
Since I quit Facebook, I've noticed my screen on time is pretty much halved, and I have my foot halfway out of Twitter at this point too... So without social media my phone becomes very utilitarian and better, faster performance and all that nonsense doesn't matter as much. Cameras seem to be at a reasonable level of fidelity nowadays, too.