Interesting but how up to date is the OS? Can I expect current Android versions to show up over the next few years? Are the vendor customizations good or bad?

I tend to stick with Google phones because I like the stock Android experience. I've heard Sony isn't too bad. I really didn't like what Samsung did to Android but I last experienced it over a decade ago.

OEMs these days usually give 3 yrs of OS updates, though usually not as fast as Google. The phone doesn't become a brick after those 3 yrs though, all apps and tools remain updated independently of the OS, actually Androids receive those software updates for longer than iphones. I've got a few very old phones and tablets that are still as useful as on their 1st day, though well behind the current stuff.

Not to mention the fact that AOSP-based distributions like LineageOS can be used to keep the Android version on older hardware up to date for a long time after the vendor has given up on it, providing OTA updates to keep the device current. The real limiting factor ends up being the relatively low amount of memory in very old devices (512KB-1GB used to be common around 2010-2011, Android can still run on this hardware in a limited fashion but 1.5GB or more is preferred).