How much truth is optional?
Protestantism asks how many of all those pre-Reformation beliefs can be jettisoned and still have Christianity. Except in a certain special context, Catholicism isn’t very interested in how few truths one can get away with believing. Instead it wants to know all of them. Tell me everything, everything! Are there more?
If anything, I think what J. Budziszewski says about Catholicism is even truer of Orthodoxy.