I’ve resisted the idea of letting my calibration tool change my display brightness and profile on-the-fly, as I was taught that consistency was the ultimate goal of color management. What benefits come with Spyder X profile switching functions?
If you work in a totally controlled space, with no variation of the lighting (which is recommended) then there is no need to try these features. However, many people must work in spaces with windows, and varying lighting, and for them, these functions are critical, for just the reason you mentioned: under variable lighting, profile switching actually produces greater consistency in what you see on the screen. It is still aimed at color management’s ultimate goal, just in a different way.