Maybe it’s not on sale everywhere, but it’s the same price as a 256GB Pixel Tablet for twice the RAM, twice the storage, and full Linux instead of Android.
Tablets are traditionally a closed design, with the OS tightly locked down. Even if that price were high, which I’d challenge it’s not aside from the CPU choice (probably by necessity), there’s bound to be a bit of a premium for early devices to a niche market.