Use FOSS. If you have a few spare ducats, throw it the way of the developers who make the software you use.
Encourage the use of FOSS at your work. Be a gentle evangelist for FOSS when it is appropriate and useful.
Everyone doesn't have to use Arch and hand code their own kernels to win. All that has to happen is for Microsoft and Apple to realize that their current superiority is under siege and that if they do not comply with the desires of their users they will eventually be ousted.
Hopefully more people will start to use Linux. When there are more Linux users than Apple users that will be a good start, and with all of the enshittification Microsoft is adding to their flagship os, it has never been easier or more convenient to try a Linux.