refactor(more): avoid Box<dyn Write>

[xtqqczze]

No description provided.

[github-actions]

GNU testsuite comparison:

Skip an intermittent issue tests/rm/isatty (fails in this run but passes in the 'main' branch)
Skipping an intermittent issue tests/pr/bounded-memory (passes in this run but fails in the 'main' branch)
Note: The gnu test tests/expand/bounded-memory is now being skipped but was previously passing.
Congrats! The gnu test tests/cut/bounded-memory is now passing!
Congrats! The gnu test tests/printf/printf-surprise is now passing!

[cakebaker]

Thanks!