I doubt they run on windows tbh. If they take issue with with monolithic design of Linux, then windows would be an even bigger problem.
Also, most of the devices in question are probably small controllers, incapable of running windows. (Microsoft are struggling to run it on arm so…)
ELISA (Enabling Linux in Safety Applications) Project announced that Boeing has joined as a Premier member, marking its commitment to Linux and its effective use in safety critical applications. Hosted by the Linux Foundation, ELISA is an open source initiative that aims to create a shared set of tools and processes to help companies build and certify Linux-based safety-critical applications and systems
I imagine this means they’re contributing both actively and financially to Linux.
Some thinkpads have official support for Ubuntu by the manufacturer (lenovo), which means battery optimizations out of the box, amongst other things. Might be relevant for your laptop.
I think technically what they sell is services related to RHEL and not it itself (correct me if I’m wrong).
To me at least, a big problem with it is the hypocrisy. RHEL started itself by repackaging another piece of software. Why is it not OK for others to do the same to them? Especially when the gpl license allows that, and requires them to allow that!
The Linux license allows anyone to distribute it for profit (under certain conditions). If I wanted to sell CDs with the Linux kernel I could. Wouldn’t be a good business, but I could.