Here is a thoughtful and detailed answer to the question "Did TLJ kill the SW franchise?"
Probably, yes. But it will manifest as the Five Point Palm Exploding Heart Technique. The IP will walk on for a while, seemingly unharmed, then collapse. But the blame should be shared at least as much by JJ Abrams and “The Force Awakens”.
Goodwill towards the IP has been damaged heavily among the core fans. (I don’t consider myself one of them, although I liked the series a lot as a kid, but I see what they write, the videos they post on YouTube etc.) Johnson, Kennedy and others have displayed contempt for this subset of fans, essentially dismissing them as a “basket of deplorables”. This is terrible PR, and it also shows an unwillingness to face up to the very real problems Disney have had with the IP.
Here is a section from investment website “Seeking Alpha” focusing on the absence of any guiding creative vision (comparing the Lucasfilm division with Kevin Feige’s team at Marvel):
“With Star Wars, Disney took a very different approach. Kathleen Kennedy, the head of Lucasfilm, seemed to prefer treating each film in the new trilogy separately, rather than as a single narrative. Thus, the first film was led by director JJ Abrams, but the next film in the trilogy fell to Rian Johnson. Johnson’s decision to scrap many of the narrative threads spun by Abrams proved to be one of the most controversial aspects of The Last Jedi.
When crafting a film that will, virtually of necessity, have considerable cultural importance, changing leadership willy-nilly with little thought to past entries is a recipe for disaster. The original Star Wars films were, for better or worse, guided by a single vision. For investors, thinking about narrative and vision may be a somewhat esoteric subject. But it matters a great deal when those narratives are the bedrock of incredibly valuable IP.”
A common argument dismissing concerns about The Last Jedi is, “The prequels were awful but the IP survived anyway”. Well, the prequels WERE a bit lame, but in a very different way. Their sins were ones of execution, most obviously dialogue and performances. Everything felt stiff, and the romance thread between Anakin and Padme felt very unconvincing. Yet at no point was the core story ever problematic. You could take the core scripts of the prequels, apply a little polish, reshoot some key scenes, and end up with a perfectly respectable trilogy. You can’t really do that with episodes 7 and 8 because the problems run through the scripts at a conceptual level.
The plots don’t make sense as sequel stories to the first six chapters. The single biggest problem is that they retcon the SW narrative universe as one in which good and evil take turns running the galaxy in a never-ending cycle. This is expedient for the setup of Force Awakens, and gets embraced as the core of the plot to Last Jedi. Yet this does not actually correspond with the SW galaxy at all. Palpatine’s rise to power should be seen as the Great Aberration after thousands of years of peace safeguarded by the Jedi. Episode VI was intended to be the point at which the Republic was restored and the aberration is over. Yet this is potentially problematic for making a rip-roaring sequel to Return of the Jedi.
Any plausible story needs to start out in a restored Republic with a new Jedi order in existence. But where do you go from there? Have a story of a new threat growing within the Republic? Imperial loyalists? A new Sith threat? Dark Jedi? Could work, but the feel would probably be rather similar to the prequels. And the prequels are a slightly peculiar beast. They aren’t really about “star wars” very much. Rather, it’s an action-packed mystery story about an invisible threat subverting the Republic from within. Quite ambitious and unusual, but very different in feel from the original trilogy.
So how DO you get back to the feel of the OT? Well, as in the joke about the Irishman giving directions, “I wouldn’t start from here”. So Abrams doesn’t. He simply retcons it and hopes you won’t really notice or care, because you’re enjoying the action, the snappy dialogue and the jokes. The setup for TFA makes very little sense as a continuation of the Star Wars story, because it snaps us back to the functional analogue of the beginning of Episode IV with almost no explanation. The victory in Return of the Jedi was essentially all for nothing. Jakku seems like a worse place to live than anywhere under the Empire (with the possible exception of Alderaan; would have sucked to live there). Luke’s Jedi academy was a failure and he’s a broken man. Somehow the Empire live on with greater weaponry than they ever had before.
For the first time in Star Wars, there is no joined-up thinking. This doesn’t feel like a story written by people thinking about lore, mechanics and continuity. This feels like a story written by people who understand what Star Wars looks like on the surface but none of its internals and complexities. This is a film designed by a focus group. Lucas’s prequels felt clunky but authentic. The sequels feel snappy and vibrant but inauthentic. They don’t really fit the SW universe. And that’s a big problem.
Last Jedi is an over-correction to some of the issues that TFA had. TFA felt like it was designed specifically to retread old ground with old tropes. (This was arguably the first time the series had ever done this; “Jedi” obviously gives us a second Death Star but the plot is very different from that of the original “Star Wars”). Last Jedi wants to go SO far in the other direction that it throws the baby out with the bathwater. It feels like it’s designed to be everything that Star Wars fans DIDN’T want, almost for its own sake, to make a point. You can call this bold, but you can also call it arrogant and self-indulgent. It would be forgivable if Johnson set up a whole slew of interesting new plot threads and ideas, but he doesn’t. In fact, he seems to abandon his iconoclastic mission during the scene aboard Supremacy where Ren simply reverts to type, being an oddly motiveless angry kid, and we get an utterly traditional showdown battle.
And then nothing is set up for the final chapter. No interesting questions, no cliffhangers, nothing unresolved. Other than the aforementioned question of what on earth Kylo Ren actually wants. Are we rooting for him to die? To be saved? What’s at stake? What’s motivating me to see Episode IX?
Finally: Star Wars is a somewhat formulaic franchise. The formula is what makes it successful. It would certainly be bold and subversive for Coca-Cola to start shipping apple juice in their cans, but we should not necessarily applaud them for doing so. And if I were Coca-Cola I would be very wary of dismissing the complaints of Coke fans as coming from people who don’t understand bold visionary moves.