I don't think that Edward had in mind that the tanner's grandson would entirely replace the ruling class, strip out the use of English at the top of society, end the advanced scholarship of the English monasteries, reduce the status of women to chattels (not removed until the 19th century, still not right), introduce the sort of laws we now see in totalitarian regimes, etc.

William had no blood claim to the throne. He had not been approved by the Witanagemot. The evidence for his legitimacy is entirely from one side. Edward had no business playing silly games with the throne, no matter the problems caused by the Godwinssons. Harold may, by the way, have been descended from the royal houses of Denmark and Sweden, on the female side, if that matters. William had no royal blood.

And whatever his legitimacy, it does not make the continued presence of his hangers-on's descendants at the apex of society right. It isn't cream at the top.

Penny