Gonna pop this in spoilers so that Poka's topic isn't completely ruined...
Episode 7 uses existing assets, but completely wipes the slate. What happened in ROTJ is said to basically have not mattered. Episode 9 is similar - uses existing assets, but is so irreverent to the existing movies, especially Episode 8, that anything goes.
Episode 8 is RELIANT on existing lore, because it tries hard to give a message of moving on. Without the Jedi order, understanding of its fall, who Luke was and why he might be in exile... that's all nothing without understanding. The themes that Johnson fails to land are all based on knowing where Star Wars has come from. Without that, it's just a weird movie about a master that is not established at all, weird space magic, and an hour of action and plot that has zero impact on the movie's outcome. A well-made movie, that is not.
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"Bordate is a pretty shady place, what with the gangs, casinos, evil corporations and water park." - FAHtastic