You want a Linux install to take up less RAM? Install a lightweight distro like Endeavor or regular Arch and go with an absolutely minimal build.
You want that with Windows? There are ISO’s that have Cortana and other preinstalled bloatware already removed, etc. Or you can do the same with PowerShell post-install.
The more I hear Linux purists talk the more it’s clear their knowledge of windows is either incredibly basic with no attempt to actually learn or fifteen years out of date. Usually both.