At some point you have to trust something, whether it be your software or your hardware.
Besides the telemetry stuff, it's not a trust issue. I just don't have a need for any of the packages I remove. I don't need cortana and search, I don't need Windows Defender and it's cloud features, I don't need onedrive, xbox, modern apps, etc. It's my choice, so I remove them.
Perhaps the level of run-this-binary trust is about the same for both sources, but he trusts the motivation of the random-forumer more than those of Microsoft?
These kinds of toolkits have existed since Windows 7 at least (NLite and friends). Some are the equivalent of putting go-faster stripes on your car, some actually work, some do things like https://twitter.com/SwiftOnSecurity/status/75879678600154726...
2 its open source, as in you open bat file and read its source