It’s unfortunate that we can’t access operator properties in poll. I think it is not possible because at the time poll is queried, the operator construct hasnt been created yet (note use of cls and not self) so the operator properties aren’t available. I agree that they should be since op is a construct that stores the operator properties and it is available in the UI, but it’s not possible to add it the layout context after initialization.
Interesting read on the subject checking properties in poll - #2 by guy_lateur