I'd argue it's mostly true. I've never used Fahrenheit for a pool, the pools I've used in multiple cities around the west are all in Celsius. I'm as confused about 101f as a hot tub temperature as I am about knowing if 72f is a good room temp. Like most people I know, I switch my AC to Celsius immediately, because otherwise I have to do a mental conversion any time I want to set it. I think the only F a Canadian is almost certain to use is in oven temperatures..

And the "is it for work" adage for lengths only really applies to trades.