Imagine a company building a kickass motor (4DS). Huge...

Imagine a company building a kickass motor (4DS). Huge horsepower and small weight, massively efficient.. Another company who help the design has the motor sitting on a test stand with some promising metrics (IMEC). The motor company doesn't know the first thing about building a chassis. With minimal information the chassis manufacturer (HGST) can build a car around it and give feedback to the engine designers that would make it go harder. Engine company might loan the chassis builder an engine to fit, but isn't going to send them complete blueprints.

I'm unreservedly confident HGST isn't knuckle deep in the technology like IMEC and 4DS are. HGST likely has zero insight into how the chips are baked. They don't need to know.
There's a lot more to a working storage device than just a memory chip, the systems and real world controllers are just as important.
Don't be surprised if WDC is just in this for a small sliver of the pie at a reduced cost.
All we see are the dolphins chasing the herring and the sharks circling. The Kraken might be waiting for them all to come together.

I've seen it heaps in the market. You never know what's below the water.