Apple have been exceptionally good at making money recently - but less so at being innovative (aside from maybe unifying CPUs). Apple's not afraid of losing money on Vision Pro. They're afraid of losing face in the market. They need this to succeed. They've patiently waited on the sidelines for a decade of VR - now they've leapt into the ring, they not only need to beat the incumbents, they need to build a larger ring and win in that as well.
To succeed they need the hardware (which they seem to have) - but also they need content to access once it's on your head. No content, no mass-market. Apple needs Netflix to be inside their magic-goggles way more than Netflix needs to be there. Nobody's cancelling their Netflix account as their new goggles don't support it. Many people might not buy the goggles if they can only watch AppleTV.
So why might Netflix not want to roll another client? Well I suspect as AppleTV is a direct competitor and Apple has delighted in sitting between users and their subscription providers, skimming off their %.
Apple would love to have a Keynote with Disney, Youtube, Amazon, Netflix and the rest on stage. All the big boys pledging fealty to Apple and undying support for their new shiny - but wtf is in it for them? In their shoes I'd only get inside the goggles after I'd got a very long and generous list of commitments for the future met - so if the goggles take off, I share in the rewards. I'd also ensure my non-attendance was widely noted and commented upon to provide some pressure. What's the worst that can happen? I get to sit back and watch Apple absolutely haemorrhage money producing expensive content that shows the value of the headset, but can only bring in money from the relatively small number of people with it. It's not even as if Apple can punish you for not showing support. Any time you decide you do want to create a Vision Pro client, you just announce it's ready - and Apple would have a hard time explaining why it couldn't be released.