The argument that everything the OT characters worked for has been undone is false. All they were working for in the OT is to bring down the Empire. There were no goals to rebuild the Republic, to rebuild the Jedi order. That wasn’t in the OT. Luke wanted to become a Jedi. Done. Never undone. He went into hiding, but he was still a Jedi. Leia led the Rebellion to victory and we aren’t even sure what all she did, but when we meet up with her again she isn’t just a princess in a Rebellion, she is a general in the new Resistance. Han got with Leia, had a son, broke up with Leia and is now on his own, which is more in character for Han that what he did in Legends post ROTJ. So nothing that these characters got in the OT has been taken away. Luke started a Jedi Academy that was destroyed and then went on a quest for answers and didn’t find the ones he hoped to. And they had to do it off screen because you can’t have a successful story that shows what they had and tears it apart unless you put it back together or give them something different and better. So the tear down had to happen off screen. Then we get to watch them fight and achieve something new. But the main focus of the ST was always going to be the new characters. It was never supposed to be the second trilogy for the OT characters. It was supposed to be the older actors in supporting roles to the new cast and that is exactly what we got.