You missed my point.
Canonization means that JPII is in heaven. I cannot hold that he is not in heaven. In that sense, I cannot “disagree” with his canonization.
I can still think that he should not have been canonized, on the grounds that he was not a great Pope. In that sense, I can “disagree” with his canonization.
No, I did not miss your point. I have never heard that we Catholics can choose to say or believe, “I don’t think that this particular person should have been canonized”. I have never heard of Catholics ever been able to choose one of the previous canonized saints in the history of the Church and say “The pope was wrong to canonize him/her”.
Please share Church teaching that states Catholics can “disagree” with the Pope on matters such as canonizations.