And yet as far as the overall narrative is concerned, in the context of the entire trilogy AND 1-6, episode 1 is still about him. It gets this primary character into play, immediately establishes his gravity/importance, and the symbolism and metatext of the Duel of Fates, which is the focus point of the climax, is that it's dueling over Anakin's fate.
It's not about any individual piece, it's about how they all connect to each other. Episodes 1-3 are about a Skywalker. 4-6 are about a Skywalker, technically two skywalkers. 1-6 are about the rise, fall, and redemption of a Skywalker. 1-3 set up a Skywalker as an ideal hero who fails, 4-6 sets up the son as the dramatic foil who succeeds in all the ways his father failed. The father's lobe for Padme drives the OT, while Luke's echoing of Padme's best qualities is what enables the redemption in 6. Episode 1 has Shmi tell Anakin "you can't stop the change, any more than you can stop yhe sun's from setting." We then have 5 movies of Anakin trying desperately to control everything he possibly can, to "stop the change," only to finally relinquish that power and control in the end, sacrificing himself for his son.
All the business with the Empire, the Republic, the Rebellion, and even the Jedi is window dressing. The Skywalkers, their internal struggles, the family dynamics, they are the beating heart of that saga. It's what ties literally everything that happens in that saga together.
It's why Kylo Ren would make for a much more interesting protagonist. He echoes all of those struggles in a unique way. From his perspective on his destiny, to his rejection of the familial connections; he idolized the grandfather without really understanding who thar grandfather actually was. His arc is a lot more in keeping with what made the story work, still functions as a hand-off, and doesn't have the jarring "psych! Now for something completely different" whiplash of suddenly out of nowhere handing the reigns to someone totally unrelated in the final chapter.
I just do not see how the Sequel Trilogy, in its current form, breaks this dynamic by not having Kylo Ren explicitly be the protagonist. Again, he more or less gets character development and complexity on par with a lead character and the entire storyline behind the sequel trilogy exists because of the Skywalkers. And as corny, cheesy and dumb as it was, the last movie establishes Rey as inheriting the Skywalker lineage.
It just feels like an arbitrary writing restriction to say that Kylo Ren absolutely must be the protagonist. We can talk about "execution" all day, though.