You want feels? YOU GET SOME DAMN FEELS.
So, now we have confirmation from "Zangetsu" himself: he's not Ichigo's Zanpakutō, he's neither his ally nor his enemy, and he represents the Quincy power within Ichigo. Honestly, this is some damn good character development if you ask me. Way back when Ichigo was training to learn the Saigo no Getsuga Tenshō, the merged spirit had stated the only thing he wanted to protect was Ichigo, and this is tying back into that. Hell, he was willing to fight and kill Ichigo if he became a Shinigami because he wanted to keep him from fighting, but eventually he stopped trying to oppose it and instead started helping him. Now, he's willing to step back and let Ichigo use his actual power. For being the first time we've seen him in 100+ chapters, this was handled pretty well.
As for Hollow Ichigo, hoo boy. He's Ichigo's real Zanpakutō, and that's why he's been the one saving his ass all those times. He's the real Zangetsu, and the Zangetsu we knew was suppressing him in order to make Ichigo a Quincy, but he wasn't able to suppress all of him, hence why Ichigo's had a Zanpakutō. This means Ichigo's Zanpakutō is still Zangetsu, he just didn't have access to its full power. While personally I had thought his blade was actually a Spirit Weapon, this actually makes sense, since he had used it for Konsō and only actual Zanpakutō can do that. Kubo really knows how to not retcon stuff, eh?
And as for Ichigo himself, now he can gain access to the full power of his Zanpakutō because Zangetsu's stepping back. There seems to be a theme in this arc of someone's true power being unlocked, i.e. Kenpachi, and it's only fitting that the character who literally adapts and grows on the go follows the trend. What this means ability-wise, we'll see.
Overall, one hell of a chapter. I'm really liking how Kubo is carefully and realistically explaining things in this final arc instead of going "oh I need to tie up all the loose ends? Well, uh, here's all the answers, figure it out for yourself/never mind how many plot holes or retcons it creates". While this arc started off kinda silly, Kubo is really hitting his stride with plot resolution, and I'm really enjoying it.