There’s a lot of inertia to overcome here. There’s advice online everywhere that Android may not the best platform for tablets. As someone who loved the Nexus 7, until you have a large user base that’s using the tablets, it’s a tougher sell to developers and to users especially that iPads are cheaper now than they have been in the past.
It’s an uphill battle. Google has to pay those taxes for doing such a terrible job of getting into the tablet as its own related but different market from mobile.