> On laptops: I have an X1 carbon extreme running linux, but it's entirely impratical to take outside of the house: it has terrible battery life and runs quite hot.
I have X1C (not extreme) and it has excellent battery life with Linux. Consider using TLP (https://linrunner.de/tlp/), if you want to significantly improve your laptop power consumption.
It's possible he's got an old X1C and the battery is just on it's last legs as well. If that's the case, he'd probably be better served using his M1 laptop sparingly until Linux support for it is better.
I have X1C (not extreme) and it has excellent battery life with Linux. Consider using TLP (https://linrunner.de/tlp/), if you want to significantly improve your laptop power consumption.