Investing in technology has an advantage of producing reusable tech down the line.

It is very difficult to predict which parts are going to be successful.

And if they manage to create a product definitively better that competitors (like the current gen ARM macbooks), they are going to sell a lot more than 50,000 per year. There are single companies which can afford to buy 50,000 units.

I think Apple would only invest in the tech that you listed if they also want to get into the cloud businesses. Other than that, I don't see it.