Okay, I know I'm months late here, but I'd really like to give my two cents.
I loved The Last Jedi. It's not perfect by any means, but I really enjoyed it. Sure, a vocal minority disliked the movie, but it was the same thing with The Empire Strikes Back. At the time of its release, both critics and movie-goers were very upset with it due to its different tone, unresolved ending, and basically the entire story.
It's hard for us to imagine this now as everyone claims that ESB is the "best of the SW films" but we're also seeing it as part of a completed trilogy. Seriously, if you can find professional reviews and comments from 1980 (good luck with that!) in newspapers or magazines, you might be surprised to see how unpopular ESB was with fans and critics who loved A New Hope and expected more of the same.
Plus, perspective can change over time. We have evidence of this now with some very loud YouTubers who bemoan TLJ and yet continually praise the prequels. When someone says that The Phantom Menace was a better movie than The Last Jedi or that Jar-Jar Binks was less annoying than Rose, we're obviously seeing firsthand a case of "time heals all wounds."
As for TLJ and some of the complaints...
The Casino planet was a little silly, but certainly no worse than there being a
1950s-style diner in Episode II. Yes, the message was heavy-handed and I'm sure there was a better way to convey it, but I honestly liked the gray moral areas they were discussing, especially how arms dealers are playing both sides.
Leia floating in space makes sense when you consider that Luke would've likely taught Leia a few things over the years. Remember, she was considered powerful enough to be Obi-Wan and Yoda's second choice if Luke died or turned to the Dark Side. And she didn't "fly in space." All she would've needed was a tiny push with the Force and she'd keep going (because that's how outer space works).
The only reason I somewhat dislike this now is because of Carrie Fisher's death, so Leia dying here would've worked nicely. Better yet, she could've gone on the kamikaze run. Unfortunately, no one knew Fisher would die when she did.
What Luke did really fit his character. He's never been particularly great with a lightsaber. How could he be? What lightsaber training did he get? Obi-Wan had him block blaster shots from a droid and... then nothing until he fought Vader in ESB. This isn't even a case of "well, he probably got some training between ESB and ROTJ" because WHO would've trained him? Who would he have practiced against? All the Jedi were dead or in hiding. Luke doesn't even return to Yoda to finish his training until ROTJ and by then Yoda is dying.
No, swinging a lightsaber doesn't mean he knows how to use it. Han cut open a tauntaun with Luke's lightsaber, but he sure as hell wouldn't have been able to duel with it.
Luke survived his first fight with Vader only because Vader wasn't really trying (it's pretty obvious when you watch ESB that Luke was being tested) and Luke was able to beat Vader in ROTJ only after accessing the Dark Side of the Force. Luke was barely holding his own until Vader taunted him with turning Leia to the Dark Side, and then Luke used his anger to fuel himself. I think Vader was actually surprised, and so was Luke when he realized what he was doing.
Luke's strength in the Force was less about combat and more about manipulation, both of objects and people. He used that to deal with Kylo Ren and gave the Resistance time to escape, which was all he was aiming to do. The people who wanted some crazy, Michael Bay-like combat scene with Luke destroying everything in his path like a Force-powered tornado really, really don't understand his character.
And even if Luke did want to fight Kylo face-to-face, how would he have done that? His X-Wing had been submerged underwater for a long time (in ESB, Yoda raised it out of the swamp immediately after it sank, not years after the fact) and there's no telling how long of a flight it would've been to get there, even with hyperspace speeds.
Even if we assume Luke someone managed to get there in time, there's no way he could've physically handled the attack ordered by Kylo Ren where every vehicle spends several minutes firing everything they have at him. If Luke had actually been there, he would've been toast.
Finally, there's the one complaint that really ticks me off every time I hear it: "Why didn't Admiral Holdo just tell Poe her plans?" Why? Why would she?!
Holdo is an admiral. She is Poe's superior officer. In the military, you DO NOT openly question your commanding officer. Your job is to shut up, say "yes sir!" and follow orders (unless the orders have you committing a war crime, in which case you have to report your CO).
But even if Holdo was going to tell someone, why Poe?
Poe just got demoted for disobeying direct orders (from Leia, no less) and getting all of their bombers destroyed and bomber pilots killed. When Poe first meets Holdo, he pretends he was never demoted (which Holdo calls him out on) and then proceeds to tell her how she should run things. When he doesn't get his way, he throws a temper-tantrum, kicks over a chair, and behaves like a belligerent child!
So no... not only was Holdo justified in NOT telling Poe purely based on the chain of command, but she didn't want to reveal information (she knew there was an info leak on the ship or somewhere in the fleet) to anyone, least of all someone like Poe who'd already shown he couldn't be relied on to follow orders.
Probably the only reason Poe didn't get thrown in the brig for his display of insubordination (or executed for his mutiny later on) was because of how short-staffed the Resistance was. In the real world, Poe would not have been anywhere so lucky.
What's amazing is that later on when Poe tells everyone to "disengage" or "retreat" from their attack run (while on the salt planet) and Finn argues, Poe replies "that's an order!"
Right, so now you expect orders to be followed. How hypocritical.