This product is exactly how Google improves Gemini. For better or worse (I'd argue worse) Google will be putting these devices in classrooms and everywhere else to train Gemini.
My take is related but different. I believe that Google believes the customer's for these "premium" Googlebooks are the kids who used Chromebooks all their school years, and are now graduating school, getting into university, or getting into their first job. Google is presenting them an option, that feels familiar, but is also premium. The next level. The big-boy upgrade. Familiar but Better.
Except that Chromebooks are widely reviled as cheap, laggy garbage plus a negative mental association with tedious schoolwork. If anyone buys one, it'll be in spite of the brand association.