I believe the plan behind the Chinese characters in Unicode was always that different hanzi-using languages had different renderings of certain characters, and that rendering it properly would be up to the font.
Yes, but that was botched from the start. Latin alphabets include various "font variants" in unicode, you can write C, ℂ, ℭ, 𝒞, ⠉, 𝐂, Ⅽ, 𝙲 and maybe a few more…
I guess the accusations of Unicode being somewhat centered on western languages do have a point.
Was. Whoever thought it a good idea to merge letters with similar shapes to same code points must’ve been drinking way too much ancient Chinese civilization kool-aid.
IIRC, ISO-10646 initially preserved each of the 16-bit national codings for Han characters (including three separate Chinese encodings). I don't know if that has been retained at all in later versions of the standard and a cursory reading of the relevant wikipedia pages is not informative.
The original motivation for the efforts that resulted in Han unification was to help with library and bibliography management (some of these efforts were by non-CJK speakers). One of the original design goals of Unicode was to be able to represent all of the characters in existing character sets uniquely (so two distinct characters in some charset requires two distinct characters in Unicode), and another design goal was to be able to facilitate conversion between different character sets representing the same script. This dovetailed nicely with the existing efforts to unify CJK scripts for bibliographies, hence Han unification.