In terms of Creeper scaling, note that the damage that Creepers are stated to deal as a maximum on the wiki is really more theoretical, as you'd have to essentially be inside the mob itself for the attack to deal that much damage. I've tested this more than I'd like to admit, and I could consistently get Endermen to survive Creeper explosions, with a little bit of health remaining, despite the fact that Creeper explosions are supposed to do 43 damage to an Enderman's 40 HP. That was when a Creeper + Enderman were within the same block too, so I doubt they could get physically any closer. It's a similar case for charged creepers, where they can't do their maximum theoretical amount of damage even when in point-blank range to the opponent, and another reason why hit point scaling is wack. Also, the Ender Dragon takes essentially 1/4 of the damage dealt if hit anywhere except its head, which means Ender Dragons should be able to take multiple Charged Creeper and even Wither explosions without dying.
In terms of Ender Dragon AP, I feel like the argument for using Netherite blocks was missed. The Ender Dragon is programmed not to be able to destroy End Stone, Obsidian and Iron Bars because these are blocks native to the main end island. Netherite Blocks, being a block that is as durable as Obsidian (or at the very least capable of tanking charged creeper explosions like Obsidian) can be destroyed by the Dragon. There's other examples of this too - it can destroy Iron Blocks but not the far less durable Iron Bars. End stone bricks, which should be comparable to end stone both in terms of the time it takes to mine and common sense, can be destroyed by the Ender Dragon.
If people have problems with using Basalt for the calcs, which would probably invalidate 8-B results, then that's a separate problem. However, I see no problem with the theory of the previous boss scaling.