Um, no. It was never disrespectful whatsoever. He encouraged using English names and this is simply how his colleagues and contemporaries, respectfully with the titles, referred to him and called him.
In fact, as two quick random examples, these books and publications were authored and published during his lifetime by those who revered him and used exactly that name:
Confrontation: The Existential Thought of Rabbi J.B. Soloveitchik, Ktav, 1992
Rabbi J.B. Soloveitchik on Human Knowledge: Between Maimonidean and Neo-Kantian Philosophy, Modern Judaism 1986