I haven't used Windows in ages but there used to be popular tools that were used even by not-so-very nerdy, more average folks that would search your PC, indica

I haven't used Windows in ages but there used to be popular tools that were used even by not-so-very nerdy, more average folks that would search your PC, indicate all the problems they found with wasted disk space and security, and offer fixes. It still goes without saying that without a resounding "I understand the risks and still want to use this inherently insecure feature" things like these should not be enabled by the OS manufacturer / vendor.