I generally agree with the first point. As to the second, this is clearly designed for people who will have the technical know-how to facilitate custom CSS, browser extensions, reader modes, and other assistive technology.
Considering its branding is entirely centered on late night socialization, I feel low-contrast dark mode is precisely the aesthetic that fits its identity.
> people who will have the technical know-how to facilitate custom CSS
I think anyone with access to an LLM doesn't necessarily need the technical know-how. They can just ask as an extra step for a design check including text contrast.
> I feel low-contrast dark mode is precisely the aesthetic
Agreed, and I like it too, if legible.