""Whatever differences on points of doctrine may exist amongst the different denominations of Christians, all should be united in the bonds of charity, all should pray for one another, all should be willing to assist one another; and, where we are compelled to disapprove of our neighbor's doctrine, let our disapprobation fall upon his doctrine only, not upon his person.
https://en.wikipedia.org/wiki/Demetrius_Augustine_Gallitzin
The real world result of such teaching can be viewed first hand in South America, since that has been the teaching since Vatican II.
In Brazil, the largest population Catholic country (all of Central and South America was Catholic) , today as many Protestants go to "church" on Sundays as Catholics,
and they are growing fast in numbers by the day. This is happening all over South America, where there were no Protestants before. To be clear, in Brazil, only about 7% of Catholics go to mass, and that is to the Novus Ordo, so the majority of Catholics have fallen away from the faith altogether AS A RESULT of the indifferentism taught to them by the Vatican II policy which is identical to the quote by Fr. Gallitzin above.
The Spanish preserved their country and possessions (all of the America's South of the USA) from the heretical Protestants with the sword and spread the faith throughout the world. The Vatican II religion has dissolved the faith from all of those countries with the white flag of indifferentism.