with the RAM still at 4GB the 12.9" upgrade from last year to this year isn't worth it, unlike the 9.7" to 10.5" which jumps from 2 to 4GB RAM
I wouldn't say it isn't worth it. I think that depends on what one considers "Worth it." The other notable features, you're still getting the added Tru-tone display, the 120 HZ refesh rate, 600 Nits of brightness (2015 12.9 had 424 Nits), upgraded camera with flash. The new 12.9 will sync at USB 3 Speeds, and has lower reflectivity at 1.8 % over the older 12.9.
The upgrades are there, you just have to appreciate these additional features.