This seems like a bad plan. While Fire OS has always been an outdated mess of AOSP, it still supports large pool of apps with sideloading. This is also probably expensive to build and they continue losing large amounts with their Alexa stuff. I wish for a third option besides just Android and IOS ,but I'm not holding my breath for this being it.
I don't see Google raising that storage limit anytime soon. They've spent the past 2 years years trying to get rid of storage requirements on their end. They combined drive, email, and photo storage in the same storage limit. They're about to start trimming inactive Google accounts. The plan here is to push people into the higher 1TB plan which might be more profitable for them. I'm amazed the price for the plans have held steady. I'd expect a price increase from either Google or OneDrive.