Is it in PayPal's interest that Libra succeeds? It seems that they would be competitors. They might just have backed it strategically to somehow have a stake in it if it takes off big time. Given the pushback they could now bank on the whole thing failing instead.

The point of the cryptocurrency was to decentralize Libra amongst several actors, such as Visa, Master Card, Paypal, etc

If done, Libra would have been the common interest of all those actors. That was the goal of the project.

That doesn't seem to contradict what I said? Sure, PayPal wanted a stake in this assuming it would become a success that they couldn't stop... but they may still be better off if Libra doesn't become a success in the first place.

So the plan was to form a cartel in public?