Qualcomm are slowly but steadily improving Linux support for the X1/X2 Snapdragon CPUs (such as the qcom-hamoa-ec driver in 7.2), so it's still a wait. I think there's some challenges with Secure Boot and the firmware with these Lenovo devices though.
Unlikely. I've been daily-driving the predecessor (X13s). While it's usable and technically all drivers are there, it's far from "without pain" due to endless number of small but annoying quirks. Just to give you an idea: boot fails 4 out of 5 times, external displays aren't recognized unless plugged in/out several times, sporadic resets during overnight sleep, etc. On top of that speakers will sound prohibitively tinny due unimplemented software-side speaker protection. I haven't tried T14s, but at least the audio issues will still apply there.
Apple devices supported by Asahi are a far more polished experience.
The effect is understated there, perhaps because Apple speakers are actually somewhat usable without this feature. For the X13s, the speakers might as well not exist in the current state on Linux.
Complexity in the name of cost cutting. A hardware power limiter based on temperature would cost... $1? A thermal pipe from speakers to case acting as a radiator would be... $5?
I just setup Gentoo on a Lenovo laptop last week. It was the least painful process for a Linux laptop of my entire career. Everything just works. Even sleep and the fingerprint sensor for sudo. LLM tuis replaced Google entirely.
I can't even say there was any pain whatsoever. The experience is now more akin to MacOS circa 10.6.x years.
Driver support for that particular Lenovo is 100%. You just recompile. The issue is more to do with the CPU not being as good as say an AMD AI Max or an M4.