And you seem to be a bit confused about code points and graphemes clusters.

UTF-32 grapheme clusters can easily be six or seven code-points long. Examples: modifier characters, flag/regional-indicator sequences, (and to a lesser extent, combining characters).

Why does it matter? Because you can't insert a linebreak in the middle of a grapheme cluster.

So even after converting all of your UTF-8 text to UTF-32, you STILL have to deal with multi-character code-point sequences.

Madness!