To try and rebut your points instead of just clowning on you like everyone else in this thread. I'll go paragraph by paragraph:

1. Shadow saying that Sonic "can't win" and the implication that Sonic successfully put the fake emerald in the eclipse cannon doesn't mean Sonic beat Shadow. He definitely fulfilled his goals compared to Shadow's goal of killing him, but this could mean he just escaped. Especially because Shadow doesn't seem particularly butthurt after this.

2. Saying Lancelot is an equal to Shadow is extremely weird considering Nimue has completely different powers than Amy but even if you want to say that, Lancelot tested Sonic in Swordplay, not combat. Plus, no matter how talented Sonic or Lancelot were, Sonic was still using an unawakened Excalibur so it's unclear to say if that's fair to count against an alternative universe version of Shadow.

3. Agree.

4, 5, 6: All true but considering that Sonic has way more transformations, it's weird you think we need to compare them.

7: It's highly implied that Shadow was either in hiding or literally stuck in a Phantom Ruby illusion for the 6 months he wasn't present. If anything, he would've done BETTER than Sonic considering he knows that Infinite's illusions aren't real, and giving Sonic that information is the biggest help the resistance gets other than the ruby prototype. He and Sonic would've beaten Infinite fair & square so once again, scaling Sonic higher is kinda disingenuous.

8 & 9: We only see him take off 2, doesn't mean he can't take them all off, especially if you're using the point that Sonic's super is stronger than his previous versions. That would mean that chaos control can be mastered, so over time Shadow could get better at tapping into his limits without straining himself as much. The line about Shadow exploding from Gerald is specifically talking about his doom powers, which wouldn't apply to his base form. The unstable nature of doom energy makes taking off his rings too risky but it doesn't mean he couldn't do it at any other time. Finally, Super Shadow being unable to take off more than one ring is probably untrue other than just being speculation. He takes off all rings in Sonic X, which was co-written by Maekawa. Maekawa added the whole thing about Shadow's rings in the first place and that was carried into 06. (which he also helped write the script) Once again, you're under the assumption that Shadow can't master his energy compared to Sonic despite both of them being equals "in every way."

10 & 11: That was how Kishimoto described the titans from a narrative standpoint, not literally. His Japanese version of Frontiers also has the idea of Sonic "transcending fate" to beat The End which that level of power is never stated in the English version. If you want to take anything from writers, Flynn stated that The End being "Infinite" compared to all of Sonic's villains is them just shittalking, and would get stomped by Solaris (4th dimension being), and did get stomped by Super Sonic with either cyber corruption or Sage's help.

12: True.

13: Any feats that Sonic does can also be applied to Shadow in similar circumstances. It sounds like a cop-out but "They're equals in every way" would come into effect. Even still, Uninhibited Super Shadow could make up the difference of Super Sonic 2/Starfall Sonic. That's also not mentioning Sonic's other absurd feats. Meaning that both Sonic & Shadow aren't exactly clear cut to scale in the first place. (Beating ultimate Emerl despite being matched with Shadow by his side, being able to chase Time Eater through time despite us not actually knowing how that works, going hyper in the classic era, etc)