I want browser vendors to include a scheme toggle. Until this is present, I want website owners to include a scheme toggle. I don't care about the ideals while they degrade user experience for no good reason. Your website won't break once the browser toggle is implemented.
> I don't think it's fine in your scenario, and the current state of things.
I have no idea what you're trying to say. What I said in your quoted example is: you don't have to include multiple color schemes. Why do you think it's not fine? Why do you expect website owners to include multiple color schemes?
> If we require websites to individually provide their own toggles, how will the user know a toggle is even available or not? It creates an inconsistent UX where some websites have toggles and others don't.
Inconsistent UX is better than non-existent UX. You're asking for website owners not to include a toggle. How is that better than having inconsistent toggles which force me to change my whole OS color scheme just to change the scheme of your website? You're not explaining any advantages this has for the UX. Because it's pretty freaking terrible UX to do so.