At Least Rian had Mark and Carrie together in Last Jedi. Although I’m sure someone will point out the story context of Luke faking being there through the force. Astral projection.
We saw Lando separately in the third one. But Wedge popped up on the Falcon? Wicket and his son on Endor.
Not to mention Artoo and Threepio in all 3 of them. Chewie. Yoda in the second sequel. There are elements of nostalgia just not enough I suppose.