Google keeps their own hardware updated quite well, I liked the monthly security updates.
With regards to the rest of the tablet market, basically only Samsung and Lenovo are left, and Samsung lost me as a customer a long time ago.
I've been looking at the iPad Air 3 recently and while it looks nice, I just fell in love with the Apple pencil. The fact that they update even their ancient hardware is just a huge plus -- that's commitment to the customer.