is it worth to upgrade phone every year?

As others mentioned, it's not worth it unless you have lots of money to throw away.

You probably hear that new cars depreciate in value a lot but did you know smartphones and some computers can depreciate in value even more (in terms of %)?
Back then, it might make sense to get a new smartphone after 1-2 years but now, technology for smartphones have started to slow down. People have started to upgrade slower than before (some statistics where the average used to be 2 years is now closer to 3 years or something).

Even budget smartphones these days can kind of hold its own against flagship smartphones for most users. It's just good enough for most people. Not everyone needs the best camera or best processor or most memory/storage.