Refs #30573 -- Noted to avoid "simple" & co. in Writing Style guide.

Co-authored-by: Tobias Kunze <r@rixx.de>

docs/internals/contributing/writing-documentation.txt

@@ -129,6 +129,12 @@ Instead of:
 * his or hers... use theirs.
 * himself or herself... use themselves.
 
+Try to avoid using words that minimise the difficulty involved in a task or
+operation, such as "easily", "simply", "just", "merely", "straightforward", and
+so on. People's experience may not match your expectations, and they may become
+frustrated when they do not find a step as "straightforward" or "simple" as it
+is implied to be.
+
 Commonly used terms
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