I do think that using the phase changes of water as the sole point of comparison is a bad argument.
Why? Water is extremely important to life and very abundant. The phases changes of water are something that you are confronted with in every day life, all the time.
For most people, the interaction with temperature is through the weather, and I don't think Celsius is inherently better for that.
I do, because the temperature being above or below freezing is a very important boundary. Freezing temperatures means slippery roads, frost on windows, car locks freezing shut, etc. A lot of our interaction with the world outside is affected by the temperature being below or above 0ºC. By comparison, 0ºF is completely arbitrary, nothing changes when you cross that boundary.
I like that in Fahrenheit 0 is a cold winter's day, and 100 is a hot summer's day.
10ºF is also a cold day, so is 20ºF and 30ºF. Just like 90ºF is also a hot summers day.
I find that more relevant in day-to-day life than the phase changes of water.
None of those seem relevant to me. I don’t need a round number to know that 37ºC is a hot day. There is no significance to 100ºF. 99ºF is also a hot day and so is 101ºF. Nothing interesting happens when you cross the 100ºF threshold.
When you cross the 0ºC or 100ºC, potentially dangerous things start to happen of which you need to be aware.
Well, there is this guy