Actually, The Last Jedi completely sidelined the black male lead of Star Wars to drum up more sympathy and screentime for the white male antagonist (who is arguably now the True Protagonist of the trilogy--while he’s Evil, he’s also the one the plot pivots around the most, and if he has a Redemption Arc in the third movie, then the main overarching plot was Ben Solo’s Return to the Light). At the same time, the Vietnamese female supporting was given a shallow and self-contradicting plotline that turned out to be little more than being a love interest, and the Latino hero from the first one was put into his place by being made to show respect for a white woman (by performing actions that didn’t fully mesh with his character from his first movie). Furthermore, Rey’s potential development was given a hamstring by a sudden obsession with redeeming the aforementioned tortured white evil guy (because he’s handsome and has an eight-pack), and the promise of a reckless-and-relentless space-fantasy-heroine who protects the weak was replaced with a soft, hand-touching girl who immediately felt sorry for the murderer who had tortured her two days prior. Furthermore, Carrie Fisher was needlessly sidelined for two films in a row, and Mark Hamill’s most famous character was twisted into something that would suit the white-evil-boy’s narrative. Almost everything the non-white characters did had little-to-no impact on The Last Jedi’s plot (when Poe and Paige blow up the Dreadnought and save the fleet, their actions are criticized and condemned), while the new white female ends up saving the day without having a story arc or any real development. Plot holes repeatedly open up to let our characters pass through without a challenge (diminishing their accomplishments even when they have them), the story structure is flimsy and doesn’t properly support the fantastically-diverse and talented cast, and a lot of the more memorable parts were ad-libbed by the actors and actresses and accepted by the overacclaimed director. John Boyega was all but erased from the promotional material, Kelly Marie Tran’s character was never fully explored, and Rey never got to have a proper training sequence or even a proper philosophical debate--the one interesting scene with her and Mark Hamill was left on the cutting room floor, and the legendary actor of two generations past never had any proper positive interaction with the shining star of this current generation. Then again, you can probably count the instances of positive interaction in The Last Jedi on your fingers, but...what do I know? Tiny-brained, right?
That being said, yes, there are a lot of idiots who criticize The Last Jedi for stupid reasons. But most of them were criticizing The Force Awakens for similar reasons, and the backlash wasn’t as intense; the difference was that The Force Awakens used its diverse and talented cast effectively enough to show promise and potential and earned a fresh new fanbase. Daisy Ridley’s grit and determination, John Boyega’s wild enthusiasm, and Oscar Isaac’s endless charm all pushed their characters into the hearts of millions. The Last Jedi gave all three of them subpar scripts and evoked tepid performances--there isn’t a single moment of The Last Jedi where Daisy Ridley delivers a line as poignantly as “I never knew there was this much green in the entire galaxy”, or as memorable as “No, no, no, the one I’m pointing to! No!”, or even as memetic as “The garbage will do!” John Boyega never leans into the camera with the same intensity as he did when he delivered the line, “You don’t know a thing about me. Where I’m from. What I’ve seen”, and he never gets to smile at someone the same way he did every time he bumped into Rey. Oscar Isaac’s confidence and calm is wiped away for bravado and ire. Heaven knows what Kelly Marie Tran might have been allowed to do with a proper script and director, but we know that Lupita Nyong’o was wiped aside for a brief cameo of vague warnings.
Again, I would love to defend The Last Jedi against the racists and misogynists who plague the fandom. But their arguments are petty and don’t matter, and there are actual arguments to make against the film--and these ones are continually ignored. People can blather on about Leia floating and a lack of Snoke backstory all they want, but those are trivial pieces that smart fans can wipe aside in an instant; it’s harder to explain why an ultra-rich and exclusive casino would just let two scruffily-dressed strangers inside without money or ID, or how larger ships can’t outrun smaller ships while in the vacuum of space (remember how the bigger ship outran the smaller ship in the very first shot of the entire franchise?).
The pathetic “fans” can’t ruin Star Wars. What can ruin Star Wars is a corporation that’s so greedy for money and so careless about its products that it will churn out a three-part saga in a five-year-span without having a consistent story set in stone from the start and turning the project over to an inexperienced director and writer before the first part is even released--especially when he’s a middle-aged white man being tasked to write a story starring a white woman and a black man. This goes for all of them, really.
Tying this all back to the OP...Lucas tried. He did his best with his limits and he always tried to go for new things. He pushed for racial diversity in his galaxy and he drew from every culture, language, and speech pattern he could find. He warned about the greed of corporations and the malleability of politicians, and demonstrated how a determination to protect what we believe to be important could be twisted to evil purposes. The new saga is...a warning against the sudden appearance of well-armed Space Nazis from remote regions of space, and how even if someone beats up you and your friends and stabs his own dad, you should still give him a chance because...he’s pretty? I guess? And you’re a woman? So...gentle girl, damaged guy? That’s a story.
Maybe this should have been posted to the TLJ thread, or a new thread created, if so, please move them.