I dont understand how ex-Nokia devs could have built a phone like the N900 and then just walked away from it for 15 years
But yes, the N900 was pre-slidey-smartphone peak brilliance.
What I would like is apps to pervasively support a keyboard. For instance, in most Android messaging apps, you can't even press "enter" to send a message, so if you want to use a physical keyboard, you have to type the message and then poke the screen to send.