It is rather because there are a great many things in this world too sacred to parody.

If Browning could really convey to the world the inmost core of his affection for his wife, I see no reason why he should not.

But the objection to letters which begin "My dear Ba," is that they do not convey anything of the sort.

As far as any third person is concerned, Browning might as well have been expressing the most noble and universal sentiment in the dialect of the Cherokees.

Objection to the publication of such passages as that, in short, is not the fact that they tell us about the love of the Brownings, but that they do not tell us about it.
Upon this principle it is obvious that there should have been a selection among the Letters, but not a selection which should exclude anything merely because it was ardent and noble.