XT-20/2 will still receive Kaizen updates until the lines are refreshed.
XT-1/2 have higher magnification, so the EVF view looks enormous.
XT-1/2 have more physical controls if you prefer dedicated dials/buttons compared to reprogramming FN buttons. For some people, this is a make/break pref.
16MP is no slouch, but the bar is now solidly at 24MP for APS-C cameras. You get some improvements at high end, and access to the Acros film simulation.
Not trying to lean you one way or the other, just some considerations to ponder.