For LC:
2020+: new front differential design…maybe better/stronger differential carrier??
2018+: KDSS bolt change, automatically power-folding outside mirrors, late-2018s have new radiator design, late-2018s have capacitive touch screen on center display, powered lift gate, non-mandatory rear entertainment, newer transmission software (flashable on 2016-2017), and new key (very cool) design.
2016+ LC also gains bigger front brakes, 8-speed auto, semi-aniline leather of the LX, and has better buttons arrangement than prior years.