For all MS Windows Insiders:
I updated my Windows Insider Build to 18329.19H1 (previously 18323.19H1 that had the MWB issue). Yes I experienced the anomaly as well. I reported it through Feedback Hub.
So far, after updating to 18329.19H1, all the "off" settings are now fixed.
I'm wondering if the MWB glitch was due the changes and implementation of the "Windows Security App Experience" that was announced when 19H1 was released?
See here: https://www.bleepingcomputer.com/news/microsoft/windows-10-19h1-update-to-introduce-windows-security-app-improvements/
See the latest build Blog here: https://blogs.windows.com/windowsexperience/2019/02/01/announcing-windows-10-insider-preview-build-18329/
Flight Hub on build status here: https://docs.microsoft.com/en-us/windows-insider/flight-hub/