That was never on Kubo’s mind. He just did what he wanted to do, but he had a bad habit of introducing new characters when he didn’t know how to move the story, which resulted in the arrancar arc lasting so long that I’m not even sure saying it lasted a decade would be exaggeration or not (that and splash page abuse to pad).
Kubo’s big mistake was going further in the supernatural lore and getting the characters away from the human world, because the hollow world ended up being far less interesting and we were there waaaaaaaaaaaaaaaaay too long.
And this is STILL better than Naruto, because Kishimoto is just got awful at writing and developing villains in Hurricane Chronicles. Both Kishimoto and Kubo also have issues writing female characters, but Kishimoto was definitely worse for how often motivations defaulted to wanting to date a guy or every other woman introduced either being eye-candy only or constantly shrill for cheap laughs.
Bleach had a really interesting plot, but it went on for so long that people just forgot a plot even existed, while Naruto’s was so rock stupid and devoid of worthwhile main characters (man Naruto’s classmates just got nothing to do huh) that it constantly infuriated.
The deciding factor for me is that I think it’s totally possible to do a DBZ Kai paced style adaptation of Bleach, shaving off the fat and leaving the good bits. It had pacing issues. But Naruto’s problems were more at the core, so you need to do significant rewrites to make it work.
Oh, also worth pointing out that Bleach’s early cancellation sucked (it’s why the ending was so sudden) but it happened because a new WSJ editor wanted to push the magazine in a new direction, which is resulting in a lot of new manga today in the magazine that isn’t traditional battle manga (there’s even a psychological drama about acting and a post-apocalypse story about rebuilding society with science to defeat what is basically the anime version of ceaser’s legion, to name a few).