EXACTLY! That's exactly the point.
IF all the Christian churches were Catholic from Day One (and "catholic" = the church "according to the whole," all the churches together)--- then the Seven Churches of Asia in John's Revelation are indeed erring Catholic churches, and they are being reprimanded by a Catholic Apostle/Bishop (John).
And that's fine. There were at least 40 local churches by 100 AD, and some needed correcting by St. John, which is exactly what he should be doing as a good Catholic leader: teaching, correcting, governing.
Meddling.
On the other hand, IF the early Church was Baptist or Pentecostal or Non-Denom or something else, as claimed by some FReepers, then the Seven Churches are erring Bapt-Pent-Nondenom churches.
Except as I understand it, Baptist churches don't cotton to "authoritarian hierarchies" and outside interference upon the local congregation, so I suppose they'd just shrug off the correction and go their merry way.
Which explains why there are so many whackadoo Baptists in central Greece.
:o)
"That's a joke, son." (Quote from Foghorn Leghorn)
Explain WHY the teaching was in error to begin with!
WHY could they then NOT deliver it unblemished those next in line?