I went to look.
https://treasure1.tripod.com/sutton.html -- badly argued, miusunderstanding of sources, based on a very problematic work that presents itself as scholarship but isn't
https://hope-of-israel.org/i000111a.htm -- more extremely bad pseudoscholarship
https://www.findagrave.com/memorial/198400800/caradog_caractacus-ap... more extremely bad scholarship; in this case the author believes, among other misguided things, that Geoffrey of Monmouth wrote what we would consider, now, to be a history (what we do with the dragons I don't know)
And then there is Wolcott!
What he is doing in this list I do not know, since he uses logic, and cites his sources. I think that maybe the compilers did not actually read him carefully.
He does think that Bran, not the king of Siluria, but the other one, was probably based on a real person, which I don't, but that's a thing which can actually be argued.
Unlike where is king arthur buried and did Aeneas found Troy.
Interesting, though; since with Caradog we are dealing with one of those figures which may have historical validity, though not as the son of the Sun God. (The Brans get conflated lots.)
AND material from lots of these sources shows up in the Geni Overviews, often, because people love them.
I let it go, mostly.
For one thing, though the legends are not genealogy as we deal with it now, they once WERE part of genealogy, as it was accepted then. So they are a historiography of genealogy.
I used to argue that even the clearly legendary profiles should be connected to the Tree, as part of the history, but the majority voice was that current humans did not want to be connected to fictional persons.
so we cut them off.
But the lines are squidgy, up there at the top of the Tree.
by the way -- the way we are dealing with Arthur is to give the various Arthurian genealogies separately, as they occur in the various sources.
Such as
Arthur ab Uthyr, {Fictional, Early Welsh Texts}
King Arthur, Geoffrey of Monmouth Text
King Arthur, Chretien de Troyes Text
King Arthur, Malory Text
and, my fave, really,
King Arthur of Britain, {Fictional, Monty Python Text}