We bought a number of Carbons (Gen 9) to the office and all of them (5) have had some kind of technical problems. It's been malfunctioning fans, a motherboard that stopped working, a screen where colors were awful etc. We might have gotten a bad batch but it was not at all what I expected from Thinkpads. Lenovo's support has been great though.
I work for a big tech company with thousands of developers. We use Lenovo X1 laptops (Carbon and Extreme) and have been doing that for a few years now.
There is no systemic issue with those laptops. The failure rates are very small.
Same, everyone at our office have had issues with their Carbon. Most other Lenovo's work well, though.
Main issue most had is it chokes whenever doing something video related, which was a bit of an issue during the pandemic. And if you power it through your monitor, it will disconnect and re-connect the screen regularly. Ironic, since the monitors were also from Lenovo.. This made it impossible to have two monitors connected, since you were forced to use one of the USB-C sockets exclusively for power or it would behave erratically.