he recorded his comment with an AI service :shrug:

[flagged]

You are correct but it is not based on the sound, just if it starts with a vowel. If one listens to people speak, a common mistake, even I do it from copying the same in others, (depending on what crowd I've been around a lot,) is using an before hour as in 'an hour' though most times people will correctly write 'a hour'.