The first thing your question makes me think of is this open letter Steve Jobs wrote all the way back in 2010 titled "Thoughts on Flash". Mostly he was just s*tting on Flash for being slow and buggy and not keeping up with the times but there is one paragraph that's pretty interesting in it.
We know from painful experience that letting a third party layer of software come between the platform and the developer ultimately results in sub-standard apps and hinders the enhancement and progress of the platform. If developers grow dependent on third party development libraries and tools, they can only take advantage of platform enhancements if and when the third party chooses to adopt the new features. We cannot be at the mercy of a third party deciding if and when they will make our enhancements available to our developers.
We sort of love proving that way of thinking wrong when we can. For example, I thought it was awesome that we had ARKit support in Expo in the App Store within a week of iOS 11 (and ARKit) being released. I'd like to be able to have that near-instant turnaround with basically all new OS features, and we're thinking of ways to systematically stay on the cutting edge.
The world has become so connected and continuously updated that I think it will probably be possible to mostly achieve this over the medium term.
Also, I'm personally really excited when cool new stuff comes out for phones since that just means we can bridge it into Expo and let people make great stuff with those peripherals or features. We love doing this kind of work.