Eyes Above The Waves

The problem here is that the various Christians would like to think themselves enlightened enough to ignore the differences, and acknowledge that, in the end, they all believe in the same god and the same god's son. Holy writ can be interpreted differently, and while these differences in interpretation do make separating the various subgroups of Christianity sensible and possibly even necessary, they should not, do not mean that any of these groups is of lesser worth, or of lesser faith, or somehow not exactly how Jesus wanted it. That's what the ecumenic idea is.
That is the problem with the Pope's statement: the arrogance to believe that the Catholic interpretation of the bible and the Catholic rites and traditions that have no foundation in the bible at all are somehow better than those of the other subgroups. And that's just wrong, in more than one sense of the word.
What does that mean for the Pope? Can he acknowledge the equal worth of other subgroups and still be Pope? I think he can. Whether you're Catholic, Orthodox, Lutherian, Protestant, or whatever is mostly a matter of upbringing nowadays. There are very few actual differences in the ethics of the groups, and these differences are the only differences that count. All others do not matter - these traits may fit more into a specific culture, but they're just learned behaviour whose only merit is that of familiarity.
To be a good Catholic, a Catholic worth leading the entire Catholic subgroup, to me means a belief in Christianity and a desire to keep the subgroup moving, adapting to the new cultural context that the years bring, and to keep it from degenerating and/or sinking into obscurity. Favouring Catholicism over other subgroups, except in acknowledged personal preference, is no required trait - in fact it is an undesirable trait, because it is a sign of degeneration in the subgroup.
I have had a Catholic upbringing, though nowadays I don't even call myself a Christian. My opinion may be worth little to actual Catholics.

I agree that there are certain issues that can be ignored (with respect to calling a person a "Christian"). However, there are other aspects of Christianity that a person must not ignore when defining a Christian -- the premise that Jesus is the savior tends to be the most common one.
What I would like to know is exactly which issues the Pope felt were important enough to establish these churches as "defective". One certainly cannot think that all doctrines are "important enough", given that even various Catholic churches differ on specific aspects of church doctrine.
To extend that question, if a church were to address all of those issues, would that church no longer be defective?

I think the main issue is apostolic succession.
And by "defective" I think he means damaged in a fundamental way, but not "no salvation". For example my understanding is that if you received a Protestant baptism and convert to Catholicism, they will not rebaptise you. (Some Protestant cults will!)