Right. It's your opinion that St. Robert's opinion is the correct one.
Yes, his opinion has plenty of weight and is rooted directly in Tridentine ecclesiology, where, in opposition to the Protestants, the Church is understood to be a visible society. And it's also the opinion of the vast majority of theologians directly leading up to Vatican II. That the contrary opinion is "unsubdued" simply means that it hasn't been officially condemned by the Church, not that it's a tenable opinion.