Because he expresses uncertainty in more than one of his take-aways. He uses stronger language when he has more confidence in the idea.
"This may have..." or "I believe" or "this seems" all suggest he isn't stating fact and is instead thinking out loud about the possible implications of his experience.
In other words: it's obvious the author knows he is reflecting on anecdotes.
"This may have..." or "I believe" or "this seems" all suggest he isn't stating fact and is instead thinking out loud about the possible implications of his experience.
In other words: it's obvious the author knows he is reflecting on anecdotes.