Honestly, this question should be part of the early betting options, as well as predicting who the next World Champion will be.
Just look at this (mess):
2010 - F10
2011 - 150°Italia (Saved from being the F150)
2012 - F2012
2013 - F138
2014 - F14 T (Fan vote; Basically read like FIAT)
2015 - SF15-T
2016 - SF16-H
2017 - SF70H
2018 - SF71H
2019 - SF90
2020 - SF1000
2021 - SF21
So for 2022... I'm sure there'll be some sort of commemoration of something, either the 75th in the sport (as JPower said), or in celebration of the new rules (something similar to what they did in 2014)... or just SF22.
Personally, I wish they just went back to their F2*** Designation from the first decade of the new millennium... so something like F2022 or F2022-H
Sidenote - I actually thought they might've done something interesting in 2019 to signify the passing of Sergio Marchionne - SF90-SM (like they did with F2003-GA for the passing of Gianni Agnelli - Chairman of Fiat).