I wonder how much of this is companies distancing themselves from Facebook rather than being purely about the cryptocurrency project.
On the other hand if it weren't facebook they likely would not even have been interested in yet-another cryptocurrency. Especially if it's even not available, but just a work-in-progress thing.
I think the main issue is that cryptocurrency still has a few unsolved research & regulatory problems (like how to handle more than 10 TPS, or how to record taxes transparently) before it's ready for mainstream adoption. No big company wants to take the risk that an unsolved research problem may not have a solution, and so they wait and see how the space evolves rather than committing large amounts of resources to it. (Other than FB, who has resources to burn.) If it starts taking off they'll buy a bunch of startups and then start throwing engineers at it; otherwise they risk nothing.