I read this as a restatement of the basic belief of Roman Catholicism:
Jesus founded His Church with Peter as its head to be kept and transmitted through apostolic succession. This, in RC belief, is true only of one church.
Other churches, again in RC belief, may have varying degrees of truth, however known constitute the institution described above.
Other churches disagree of course, but RC doctrine disagrees with them.
So, it’s a restatement of the basic beliefs of Roman Catholics about the history and meaning of being Catholic - one Holy and Apostolic Church.
I see Protestants would object, but no more so than RCs would object to their basic beliefs about the history and standing of Protestant churches.
psst - Peter was NOT the lead Apostle after the crucifiction =
That guy on the right was - and he didn't die until 62 AD
This iconic painting, done back when you could become a human torch for going against the church, was one of those 'coded message' paintings...