Ah, but here's the thing (in my opinion): A friendly hello or comedic spoken ding dong is more friendly than a bell or horn. You can do nuance with a voice. You can't with a bell.And yet, in all my years riding, I've never heard anyone actually manage to achieve that instead of bawling some horrible squawk which maybe was meant to be "hello" before they raised their voice to be heard over the din of the motorists at the third attempt.
Maybe I should just keep wishing for @Tim Hall to overtake me, but it's far easier to advise people to keep it clear and friendly - fit a nice bell or a parp-parp horn.