Vatican II was totally, radically different.
For one, the scope of the changes made to the Novus Ordo were orders of magnitude larger than those made in any previous revision of the Mass. This was the total destruction of the former Rite, and the fabrication of a totally new Rite on the spot. The changes were totally inorganic: they were imposed in rather brutal fashion from above by the highest Church authority, made virtually overnight and by a small cabal of self-anointed experten, with dozens of Propers literally thrown together overnight, some of which may even have been written by protestants (it is known with certainty that many of the banal prayers of the post-VII Liturgy of the Hours were written by protestant “advisers”).
What is more, while Trent left venerable old Rites in place, the Traditional Latin Mass was declared “abrogated,” even though in reality it wasn’t, and such is essentially impossible, anyway.
For 20 odd years, the TLM was virtually extinct in the canonically regular Church. But the biggest factor was the enormous, massive nature of the changes, many of which were not even specified by the Council (but, there is an argument they could be inferred from various parts of the Conciliar text, and that argument has varying degrees of merit).
Essentially, the faithful were told that the Mass they had always known and, for the most part, dearly loved, was deficient, bad, even, stultifying, and ineffective of Grace. They were told how much they hated Latin and how they had never understood anything.
Given that the Mass was the core of the experience of the Faith most Catholics had, both the changes, and the campaign to “sell” them by discrediting the old Mass, caused many Catholic heads to spin so far, they unscrewed themselves and fell off. In essence.