Keith Robert Powell -- when you look at Medlands, what you will see is that it tells you exactly where the information it has came from. Click on the citation numbers, and they will take you down to the place at the bottom of the page which will tell you what primary document -- or in some cases what reliable secondary document -- is the reference.
Medieval genealogy, as with medieval history, is not easy. There are many places where you can get "information" -- that information is only as good as the primary sources, and the interpretation of them.
Misunderstandings, and even outright lies, can get copied all over the internet. That's not useful.
Wikipedia can be useful, when it points you to good sources. You have to check the citations to see what's going on.
And occasionally the family trees cite reliable sources. But they are not in the majority.
Alex is right, Medlands is really the place to start, when you are working in the early Tree.
And here is how I read the Wikipedia article --
https://en.wikipedia.org/wiki/Poppa_of_Bayeux --
the citation for "Christian wife or mistress" takes me to https://web.archive.org/web/20180929043557/http://home.earthlink.ne...
Which explains the sources from which we get her name (unreliable) and that she was a Christian (reliable).
The formating of the page looks hinky to me, but the citation has said that it's archived from the original -- and of course, it's on a site that captures web pages before they disappear. But I want to know where it comes from.
So I look up the author. and here he is: https://fasg.org/fellows/current-fellows/stewart-baldwin/ -- he's a mathematician who has worked in the early medieval Tree, and is respected. Fair enough.
So, THAT information seems to me to be reliable.
If you can't do that, with any site you are looking at, walk away.