It's more like Canonical looking at the progress and direction of Wayland and saying, "we don't feel this product is going to be sufficient for our near term mobile goals and would rather roll our own to ensure product delivery"
Whether or not they were correct in this thinking is possibly open for debate. There's certainly been some things they've said publicly that were debunked, but that doesn't mean the core of their premise is wrong. They are moving to a mobile strategy that AFAIK just isn't a prime directive of Wayland, but I'm not well versed in all that is Wayland so maybe someone that is can clear that up.
The petty bickering is Wayland devs and fans getting butt hurt about some things Canonical has said publicly some of which has been proven wrong as I said above. Since then, it's been a cacophony of rants from the Wayland devs/fans with general Canonical/Ubuntu haters thrown in bashing on Canonical/Ubuntu/Mir/Unity at every opportunity.
I've just started tuning it out waiting to see how it all turns out. If there's room for more than one IDE, I don't see why there can't be room for more than one compositor. May the best product win where "win" is defined as the most market share.