I have a new Thinkpad X1 Carbon, 9th generation, Ubuntu 21.10. Generally it works better than my former 6th gen.
However, when I suspend now (from the UI) (xfce4), it does suspend, apparently; the power light on the keyboard throbs, as does the red light on the back of the screen (the outer laptop cover). But when I close the screen (the "lid") to pack it away, it immediately wakes up. It's like the laptop screen close switch is backwards.
Closing the screen without suspending in advance does nothing; it just keeps going.
I have a vague memory from many years ago that there's some configuration file somewhere that controls the operation of the different inputs that trigger suspend/unsuspend behavior, but I haven't been able to find any references to that.
I've gone so far as to do the suspend and watch the LEDs while I lower the screen very slowly. They throb correctly until I get the screen folded down almost to the keyboard, but then it wakes up.