+1
Sentence 2 and 3, for example, limit how readers can interpret.

I'd like to know it is right that "how" is a relative adverb rather than a conjunction introducing a nominal clause.
Thank you in advance for your help.
+1
"how readers can interpret" is a noun clause (though it seems to be lacking something after "interpret").

"how" is an adverb, but not a relative one. In fact, I can't think of any examples of "how" as a relative adverb.
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Thank you, GPY, for another kind answer from you. Emotion: smile

I can't think of any examples of "how" as a relative adverb.
Now, I fully understand your account.