Appears they may be still working on the website as some details are still missing; looks like when you click on "detail" then full "model specs" you get a 404 page not found right now so they are probably still loading in details. And you're right, now on Toyota.com only the 2021 model shows up...
Not sure if posted already but looks like the 2022 Build & Price is up @ Toyota.com.
https://www.toyota.com/configurator/build/step/model/year/2022/series/gr-supra/
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