A lot of reworks feel like a complete retirement of the champion

When I talk about reworks, I mean complete overhauls of champions (i.e. Galio, Aatrox, Sion, Akali, Warwick, etc...).

There are a few that turned out really well, but that's not what I'm here to talk about. Why do a lot of champion reworks feel like the previous champion has been completely dumpstered in favour of replacing it with a completely new champion?

SION Let's look at Sion: his old kit was not great by any means, nor did the champion even look particularly good. I think the Sion rework was fantastic - but it isn't really Sion. This is a new champion that replaced what old Sion used to be; he doesn't look the same, and doesn't even really play the same.

Aatrox Another rework that I personally prefer to the old champion. But yet again, has a playstyle that is completely different from how the old one played. Auto-attack based? Barely. Lifesteal? Barely. Ranged harass? Only in the form of a ridiculous long-ranged knock up that prefaces the rest of a broken combo. Maybe I'm biased because I think he's really strong right now, but why couldn't this same type of power be allowed in his old kit? He sat trash-tier for years until they just threw the old champion in the garbage, replaced him with a similar-but-cooler model, and gave the new one a kit that resembles more than it resembles old Aatrox.

Galio This one I am especially concerned about. His new kit is literally the opposite of his old kit. He used to be a simple champion that was safe for anyone to pick up - linear skillshots, point and click shield, Ult that requires some set-up but otherwise was pretty 1-dimensional. And I don't think this was necessarily a bad thing. Now he has a weird, Diana-Q esque skillshot for a main damage source, he has no point and click shield, he has no healing in his kit (Which was a massive part of his old kit. Survivability is important Riot). He has hard cc in the form of 2 knock-ups and a taunt now, before he had only a taunt. Maybe I'm in the minority, but I didn't play old Galio as a tank - I played him as a control mage. Heavy wave-clear and damage, as well as zoning with ult, and sustain with W. Now he has no sustain, his wave-clear is only effective by building AP, the full commando kit he has is generally only effective when building tank, so there goes your wave-clear, and his ult can only be used to defend ally champions! Galio was never a champion that relied on teammates, but now one of his abilities is completely useless without teammates in the middle of the enemy team.

Mordekaiser This rework was one of the smaller ones you did, and it still made the champion basically unplayable. For one thing, the original Mordekaiser was a mid/top champion. And then you tried to force him bot. YOU TRIED TO FORCE HIM BOT. How can anyone in their right mind suggest that this was keeping the essence of what Mordekaiser once was? You're trying to balance him around a lane he was never traditionally played in, and that took away a ton of his solo lane power. His passive is basically worthless on solo lane Morde (the dragon gimmick, not the shield), because most of the time your mid and top laners aren't the ones who are actively looking to help take dragons. His Q has no waveclear now - that's how old Morde was played, in case no one at Riot had ever touched him. You could splitpush for days with your insane waveclear, and if enemies came to kill you, you had AOE to be able to 1v2, and sometimes 1v3. Once you get some items with spellvamp, you can one shot waves, and keep healthy if you were behind, or you could let it freeze and slow push until your enemy engaged, at which point you could heal off of them and minions. His Q now is worthless - most games you can't get 3 consecutive hits on people unless you build items/take summoners that specifically play to advantages in setting up 3 Q hits ( , , for example). His E and W are similar, and I actually prefer this W, but you can't give him power in his W and a dragon puppet that you're never guaranteed, and then make his kit weaker to compensate. This is forcing him to play differently than he used to - wait for teammates to help, play around dragon, perhaps play bot lane.

Hell, he can't even splitpush very well anymore because he has to wait for his own minions to use his W for waveclear, so he only has one ability thats always effective for clearing waves.

tl;dr Why are reworked champions so different from their initial release states, and shouldn't the goal of every rework to improve upon current mechanics instead of deleting the old champions' playstyles completely and starting from the ground up, like they have with so many reworks?