Star Wars was a worn, lived-in universe. The Last Jedi takes things further, and creates a worn out universe, cannibalising the past in the service of all-consuming entropy. Heroism and idealism achieve nothing, the only victories are through slow, grinding attrition. Sacrifice a bomber squadron to destroy a dreadnought. Sacrifice a heavy cruiser to destroy a fleet. Sacrifice a speeder to destroy a cannon; sacrifice another speeder to undo that. Sacrifice a Jedi to buy some time; sacrifice hope to buy survival.
In the original films, we saw farmers and mining outposts. Now all that remains is scavengers of old battles and arms dealers feeding both sides. The resources of the galaxy now being consumed by an unending war, human lives the only currency of value.
There's always light and dark; a dark lord falls and another rises, and the war goes on. The past is just a litany of mistakes and failures; let it burn, let it end. Keep your head down, don't dare to dream, to hope, and maybe you'll be one of the few who survives. There are no heroes anymore, if there ever were. Survive, and maybe the next generation will dare to hope again. Perhaps not. Perhaps their dreams will just make them more gristle for the endless engines of war, another resource for the wealthy to profit from.
It's just a cycle, as natural as death and decay. There is no meaning any more. The Jedi failed, the Rebellion fails, the Resistance falters. We hide behind masks and titles and heritage, but in the end, all things fall. In space, no-one can hear your call for help. There are no secret allies on the outer rim, no caged people longing to be free. There are no heroes on either side, only weapons and sacrifices.
Once, we had hope for the future. Once, we had dreams. Once, we could believe in the death of tyrants and a new age of liberty. Now we know better. We've seen a lot of strange things, but nothing that could make us keep believing there's some all-powerful force controlling everything. Hope is a story for children and the helpless; the strong do as they will, and the rest suffer as we must.
The hero stood alone against an army. He died. We can't afford heroes anymore.