It sounds so dumb on surface that someone would go such a great length to try protect a vulnerable operating system for browsing by building a forked browser and not use a modern os such as arch/linux.
If you need access to legacy Windows software, this may not be an option. I know Wine has gotten a lot better in recent years, but it still isn't 100%. There are other options as well such as virtual machines, but these often come with worse hardware requirements.
I also think it's perfectly valid to just prefer the feel of one OS over another. We live so much of our lives in front of a computer, it is meaningful whether or not that OS brings you joy.
