He may be back up for Cunnington.I don't think North needs Greenwood though? Feel like there are other clubs in much greater need of his service - Richmond, Essendon especially.
Cunnington is your prime inside ball winner/clearance specialist, you want to give him as much midfield time as possible.
Simpkin is your #2 inside mid with a strong inside/outside mix.
Thomas/LDU are your complementary offensive mids with speed and ability to go forward.
Then you have Anderson as a defensive/tagging mid and Phillips/Powell as that next group to develop.
What's the point of Greenwood?
Remember he is still recovering/treatment for cancer.
There is no guarantee he will be back for 2022. We do not know what his doctors have said, or his prognosis.
Good bit of risk management by the club imo.