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…)
Point it out explicitly in your resume. Don’t expect them to figure out your github activity on their own.
It’s definitely better to have open source experience than no experience.