Fr. McCloskey doesn't know what he's talking about - either that, or he's intentionally misusing the term, ignoring it's historic usage and connotations, redefining it towards some unspoken end.
Case in point: many (if not all) Baptists do not consider themselves Protestants, nor do Restorationists, nor Mormons. Yet Fr. McCloskey is erroneously teaching Catholics that all these groups are Protestants.
Let's just double check on who Fr. McCloskey has in the crosshairs:
"A liberal Catholic is oxymoronic," he says. "The definition of a person who disagrees with what the Catholic Church is teaching is called a Protestant."
http://www.adherents.com/people/pm/John_McCloskey.html
True, restorationists do not consider themselves Protestant. However, Fr. McCloskey is certainly using standard usage when calling them Protestant*; in fact, they are categorized as Protestant far more commonly than Anglicans; the ones who could have a real beef with Fr. McCloskey are the partisan Orthodox. Fr. McCloskey is less likely calling them Protestant than brushing over their disagreements, but then again, the subjects of his sentence are schismatic Amchurch "Catholics In Name Only", not the Orthodox, Baptistsm or Restorationists.
(*One exception are the Mormons, who, like Jehovah's Witnesses, are frequently categorized as "Marginal Christians," because they reject key Christian doctrine, such as the trinity.
I mean to make no comment on how fair these categorizations are, only that Fr. McCloskey's definition of Protestant is, although perhaps problemmatic, quite standard.)