You know what? This is completely on me. I put words in your mouth by saying that C is just as reasonable as m, l, and g, but at no point did you voice support one way or the other. For all I know, your arguments across the spectrum may be based on absolute values. Perhaps you prefer measurements for time and distance based on the hyperfine transition of hydrogen, and weight based on atomic mass.
I was pushing the rationale that arguing for metric units, which are based on freshwater at sea level, but against C, which is also based on (the perceived states of) freshwater at sea level, is an inconsistent argument. But, once again, you didn't push that narrative; I made assumptions and attributed that narrative to you.
I can't be certain that this is the exact reason, but I believe it's because metric units are based on measurements of fresh water at sea level. 1 kg = 1 litre = 1 m³ of fresh water at sea level. If fresh water at sea level has been used to standardize everything else, then why wouldn't you use it as the standard to calibrate a scale of 0 (least water movement) to 100 (most water movement)?
The problem with using K back when ⁰C were being standardized is that it's really really difficult to get your hands on some absolute zero. Also, since we generally use ⁰C to measure things here on Earth, I'd argue that the basis for C is just as arbitrary as the basis for metric. I think the equivalent of arguing for K over C would be to argue for light years or astronomical units over kilometres.
Only princes do, and only when they're super old and have ruined countless lives. After that, they're sentenced to being treated as royalty while being addressed like a normal: a fate worse than death!
I think that's wonderful, honestly. Europeans should also have the opportunity to enjoy lighting one on fire.