In answer to your second question, it represents, sadly, the legacy of a suspicious, paranoid and combative ecclesial mindset which, traditionally, had seen the world more as innately hostile territory than sacred ground for dialogue and for mutual learning, 

The high watermark of this reactionary mindset was the publication, in 1864, of the Syllabus of Errors, Pope Pius 1X's rearguard action against the encroachments of modernism. That tide began to ebb really with the Second Vatican Council.

Yves Congar was fortunate (or unfortunate...depending on your point of view) to have been born  between these events. Fortunate to have been able to express and teach a progressive theology against a backdrop of arch-theological conservatism; unfortunate in that the personal cost of this was the misunderstanding and defaming of a brilliant and prophetic mind.