Ok, I can see some logic about 2 year GC (though even for conditional LPRs, they remain LPRs until judge takes status away or LPR signs I-407).
But 10 year GC holder's status surely does not expire.
If I was an LPR, I'd rather have wording NON-CITIZEN written on DL then have shorter validity on DL. It is not like I'd be advertizing myself as a citizen when I am LPR anyways.
And while we go this route of stating NON-CITIZEN on DL, it would be actually nice if all states started including US citizenship status on all DLs like EDL in some states, but by default.