Karen Jean Tanner, Penwright -- the isolated lines are isolated so that they do not get merged into the World Tree. Often they also have locked profiles in them, as well; usually that is done because users have changed information in them, there has been vandalization, or they are controversial in some way.
You say -- "I don't think Isolating it is the answer, people need to be able to access it, chat about it, share links & info to resolve the issues."
But neither isolating nor making profiles private keeps users from accessing (that is, looking at the profile), chatting abut it (which happens in Discussions, started from the Discussion tab), sharing links (easily done in the Discussions) or resolving the issues (another thing that often happens in Discussions).
So that is actually a non-issue.
It may be, however, that you do indeed need to create your own profiles, and your own tree, so that you can put in the information and connections you believe should be in it, without having to deal with troublesome people making changes that you do not like. If that is the case, there are a great many genealogical websites that allow that -- Geni isn't one of them, but it's an easily solved problem. I have many friends, by the way, who keep both their own tree on one site, and then also participate in the Geni tree. So there's that.
But unless our mandate changes, curators are going to continue to isolate lines that they can see need to be isolated, whether, as I have said before, it's because the tree is a duplicate line in the early historical tree, or because the tree is, according to genealogical standards, either comprised of nonhumans or people who cannot at this point be connected to the World Tree with any confidence.
Both of these tools are used in order to help us keep some kind of order in a tree where, were we not to be taking care of things, sheer chaos prevails. Having profiles undergo edit wars is not helpful or useful. Much better to be discussing issues in the forum -- AND one of the things I am sure you remember that you can do is to go to the Discussion tab on any profile you are having trouble with, and see if people have already addressed the problem.
And also. Changing decisions that have been made by earlier generations of researchers and scholars is not the same thing as disrespecting earlier generations of researchers and scholars. It is the same thing as being a researcher and scholar. I myself, having been a medievalist for about 55 years at this point, work with older publications when needed, or when appropriate, but I have no trouble understanding that our interpretation of documents changes over time. All early documents, ALL early primary sources, having been written down by actual humans, are not texts that cannot be questioned. They must be not only transcribed (and transcriptions can change), but translated (and this can also change), and then must be interpreted by taking into account the author, the audience, the purpose, and the historical context. And those interpretations change over time, as we learn more or as we come to see things differently.
That also is not going to be changing. That is what scholarship is.
By the way, I haven't, myself, had anything to do with the lines that are upsetting you at the moment, but just in case this comes up: The host of Arthurian profiles, put together into trees that give the varying genealogies as they appear in various Arthurian works, were created by me. Also, I am the curator who detached the tops of the Welsh and Irish trees, which, in medieval tradition, had humans descended from the Welsh and Irish deities. Also, I am the curator who detached the upper lines of the inherited lines of High Kings of Ireland, who could not have been High Kings because High Kings hadn't been invented yet. That was me.
Finally. There is a case to be made for arguing that the unreliable pieces of the Tree should not have been detached and isolated, but simply left in the Tree as they stand, and labelled Legendary or Fictional or whatnot. My own argument for that would be that genealogical activity, a subset of history, has its own history, and the deities and invented kings that medieval people were descended from, in the documents of that time, represent an earlier understanding of what genealogy does and what it is for, and so should stay, as one of the strata of genealogical decisions and ideas. I did not win the argument. The general consensus was that only actual humans, who can be put into the Tree by using current genealogical standards, should be profiles that actual humans connect to.
Very well! I detached the Welsh and Irish deities.
Therefore.
I am no longer descended from the Welsh Sun God Beli Mawr on Geni, though I used to be. My own interpretation of this is that I AM descended from him in my reality, just not in Geni reality.
Here he is, no longer my ancestor: Beli Mawr "The Great", {Fictitious, Mabinogion}
So that would be one way of looking at the entire issue.