You should be getting Android updates until next summer (and possibly security updates for another year). Then you can still use the phone for another few years, at least. (I used my Note 3 for almost 5 years, but it didn't have a fingerprint sensor so when I started needing one, I went to the Pixel 2.)
About the only main difference between the Pixel and the Pixel 2 is that the Pixel does the HDR (high dynamic range) in photography in software, the 2 has a chip to do it, so the Pixel, in HDR mode, takes a second longer to process a picture.
Is it still a good phone? A lot of people here are still using them. I'd say it's pretty good.