Letting faucet drip does nothing to prevent freezing.
You are wrong. it gives you a bit of protection, but if it’s too cold for too long, it does not help.
The reason it works somewhat is that the water is bringing heat because the water temp is probably 50-60 degrees.
Most water supplies are underground so that water at that temp. feeds the pipes. It works. For hose bibs:
https://www.freezemiser.com/products/the-freeze-miser