> The temperature when it makes contacts with the ground beans. You could certainly boil it and then let it cool first, but that'd take a lot of extra work.

It's not so much work with the right tool: I have a button on my kettle that does exactly that, and another button that will use a little thermostat to keep it warm. Works great.

https://www.sageappliances.com/en-gb/product/bke825?sku=SKE8...