Yes, I see what you are saying.
Of course, the typical Catholic like myself would maintain that these other communities are in fact apostolic, maintaining Apostolic Succession and so are genuine particular churches.
How can you be a particular church – with a real bishop linked to the apostolic age, gathered around a real Eucharist – and yet be outside the Church? You can’t. I like how @ChristMyLife puts it, that these other churches are particular Catholic Churches that have left full unity.
And there’s the crux of the issue. Did Christ want there to be a visible principle so that these various traditions CAN find a source of full communion? I think so, and in fact, many elements of these other communities have come back into full communion with the Catholic Church. The Petrine ministry provides for this.
For example, if you think you better flourish in a Byzantine community, then try the Melkites in full Catholic communion, for example. Etc.
But I pray for the day that I don’t have to choose my current Catholic parish over the small Antiochian Orthodox church next door. I hope one day we can be in full communion, so that it’ll be easier for Catholics everywhere to experience the fullness of apostolic diversity.