Was I mean for blocking him?

I had been talking online to somebody for at least two years and than they tried to give me advice about the keto diet and their advice was factually incorrect three times in a row, so I concluded they might be trolling me and pretending to be my friend to learn my secrets and I blocked them. I don’t know if they were a real friend or a troll but I took a guess and blocked them.

Was I mean for blocking him?
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