The only thing I can think of is that because of the sudden, radical changes to the Mass and the abandonment of many devotions which occurred, people including bishops and priests began to believe that anything and everything was up for change. 
This situation was exploited by heterodox clergy and scholars. I remember one old parishioner asking the parish priest why we could now join in Protestant services when it was forbidden before the Council. The PP just fobbed him off with, "it's the Council, the Council says so". He used to answer all questions about the changes with that reply. Most ordinary Catholics were unfamiliar with the contents of the Council documents and their force so they just accepted what they were told.