The main difference between the Chrome/Windows and the current Apple situation is quite significant imo. Even though Microsoft tried their best to keep user share with IE like sneakily changing the defaults, installation of Chrome was always easy. Downloading and installation of Chrome was always an option and more importantly didn't require Microsoft's approval. That's not the case with iOS/iPadOS right now. A Chrome-like app couldn't be downloaded because Apple's not going to approve the app to be put on the App Store.
Also, from a user perspective, Safari is a good browser which manages to keep up with both Firefox and Chrome. This combination means that users don't really have that much of an incentive to switch.
To use your toast analogy, IE used to burn my toast to a sooty, carbonized block. Chrome used to do it perfectly. That's a pretty big differential in terms of performance. Now Safari isn't as bad as IE was in that era. So if it burns the edges every now and then, it's not really that big a deal simply because the user experience is more or less comparable to Chrome.
Users just want toast, but the difference isn't between great and mediocre anymore like it was with Chrome and IE. It's between very good and very good-ish.
This is precisely why I'm okay with Apple not allowing side-loading even though I would prefer greater choice. Apple's ecosystem isn't fundamentally as rotten as the Windows platform was in terms of performance. In fact, it's actually pretty good. Could things change? Sure. But as long as the user experience isn't shitty, I'm okay with the status quo.
(I use Firefox anyway, because I like its features and I'm a zealot too, but if on battery without a charger nearby, I use Safari.)
On mobile (iOS), yes. But power consumption comparisons tend to be on desktop (macOS) because the other browsers can't run on iOS at all. And I don't think Apple can enforce that API privacy on macOS because they unlike iOS they allow apps to be installed from outside the App Store.
Firefox has constantly been sussing out private APIs that Safari uses to improve battery life on macOS.
Chrome was able to outcompete everything else on Windows, despite Microsoft trying to prevent it. People actively installed it, just because it was better, also the so-called stupid users were able to install it.
If this was possible on apple devices, who knows? Maybe it would have been the end of safari.
Users just want toast, but they do prefer great toast above mediocre toast and will spend some effort on getting it.