There is a problem with this though. All Orthodox and the vast majority of Protestants can also say the Nicene Creed without reservations. That alone does not make one a Catholic.
I agree that an adult Catholic should be able to agree to the propositions in the Creed, but there are problems with this approach to Catholicism.
First, it is probable that the theological meaning of many of the propositions remains obscure to most people. For example, the phrase about God's creation of all things "seen and unseen" refers not to matter and energy, but to his creation of this world and the world of angels. Such underlying meanings are present in almost every phrase. Many people "agree" with the Creed without understanding it.
Second, the idea that "faith" means "agreement to propositions" is primarily an aspect of Calvinist theology. This approach derives from the Reformation analysis that "Credo/I believe" is primarily a matter of intellectual activity. But the Greek word used in the Creed's original form is "pisteo" and means both assent to and trust in. In one way the Creed could be translated as "I trust in One God, the Father Almighty...."
Orthodoxy and Catholicism have always held that faith is as much a matter of trusting in God than asserting propositions - that's why children, catechumens (who did not know the details), and the mentally deficient have always been held to be capable of faith and indeed sainthood.
I would argue that someone who has problems with certain propositions of faith, but whose heart reaches out in poetry and art to trust in God, can be counted as faithful.
Personally I always liked John Betjeman's summary of Christian faith - trusting that
God was man in Palestine
And lives today in bread and wine.