In a while (a year, 10 years, who knows?), the phone won't be usable any more. Then you could give it to a museum, but you couldn't sell it. (I still have analog phones, Nextels, Verizon push-to-talk phones - all useless, except for the memories. Even my Motorola V551 for AT&T is useless - it doesn't do 3G voice. And useless phones aren't worth anything.)
You can still get the February 5, 2019 update for the original Pixel, though.