I realised after a few near misses that my voice is by far the lowest latency signal method I have. If a situation suddenly seems dangerous I'll yell. Perhaps not very polite, but far more polite than hitting someone who stepped out in front of me. A bike bell probably adds a second of latency to find the bell. I'd rather use that time to brake.

The bell can be useful as a more general "I'm here" warning. But if there's any actual risk of a collision, yelling and braking are far more effective.