I've been deeply coupled to Apple since 2005 and it's safe to say they've made stabbing attempts at getting serious about this a dozen times, real serious ones too, but inevitably it doesn't matter.
The most recent one that comes to mind is Mac x VR marketing push...4 years back? Ended it complete tears, SteamVR isn't even available for Mac anymore. And it was depressingly obvious at the time there was no reason for it to work out, it was clear ARM Macs were coming very soon.
The fact that they view a stabbing attempt as a step toward being serious seems like a big part of the issue. In order to have a successful platform, you need to be dedicated to the idea of being a platform and continue pouring in the resources whether it feels like it's aligned with this quarter's business themes or not.
The most recent one that comes to mind is Mac x VR marketing push...4 years back? Ended it complete tears, SteamVR isn't even available for Mac anymore. And it was depressingly obvious at the time there was no reason for it to work out, it was clear ARM Macs were coming very soon.