For me the Wayland story is a great example of https://www.joelonsoftware.com/2000/04/06/things-you-should-...
They started saying "let's rewrite from scratch, X is too complicated "; 17 years later, they have realized the reasons for all the complexity that was written during 25 years (1984 by MIT).
I guess in around 8 years we will have 2 implementations of X.