The last driver update was for macOS 10.15, so it is unlikely there will be anything for Monterey.
A third party software called VueScan by Hamrick Software works for many older scanners.
(No relation to the company other than a satisfied user. Rescued my Minolta scanner that stopped having software after Windows XP).
John Hoffman
Conway, NH
1D X Mark III, Many lenses, Pixma PRO-100, Pixma TR8620a, LR Classic
