Not how I understood the question.
Okay. It happens.
Just because a 'denomination' name is not applied to a gathering in Christ does not make that gathering invalid.
I didn't suggest that it does. The question seems straightforward. Which of the denominations that is known to us these days is the most like the Christian churches of the first century?
And I don't consider this an irrelevant question since many, if not most, of the denominations today (Catholic, Lutheran, Presbyterian, Russian Orthodox, Methodist, etc. etc.) entertain the question when in discussions with other such groups.
Whether or not it is critical, most of them have some basis for arguing that they are more like the original church than their competitor denominations are. Catholics can point to some characteristics of the first Christian assemblies...but Baptists can do the same, pointing to other characteristics of the early church, and both like to imply that their chosen facts show them to be more like the church Christ founded than other of today's denominations.
Which of them
does actually come the closest to being like the early Christian churches?
Presumably, the one that can be shown to "fit the bill" doctrinally or that by its religious practices or organization or in some other way has a lead over the others.
I think we'd both agree that in order to be deemed a Christian, it is necessary for a person to believe little more than that Jesus is the Son of God who died for our sins and that he will save eternally those who trust in him. That, however, isn't the question here.
The question is asking about the current denomination which actually does come the closest to the religious style, convictions, activity, and everything else that describes the first Christian churches, irrespective of whether or not this makes that denomination any "better" than other ones.