I was sad when I bought a new 10th or 11th gen X1 carbon to replace my 4th gen. I configured them essentially the same, second-to-fastest processor, FHD display, no touch screen.

The 4th gen almost never kicked its fans on, especially in Linux. The new one gets far hotter, even at idle. Lenovo removed the traditional sleep mode in favor of modern sleep, which causes it to die with the lid closed in a couple days compared to over a week with the 4th gen.