Can not agree with this more, if people want to plot something that is linear please use a perceptually linear colormap! Just a one second glance at the Mona Lisa in rainbow/Jet is enough to make you gouge your eyes out. https://peterjamesthomas.com/2017/09/15/hurricanes-and-data-...

For a more technical description the information behind the newer matplotlib defaults, particularly the scipy talk, is great. https://bids.github.io/colormap/

And for those that do not like the matplotlib options, colorcet provides a wider range of alternatives that are not trash (unlike Jet) https://colorcet.holoviz.org/index.html