There isn't any deletion occuring; rather a disabling. You'll still see much of what you remove listed as Not Installed For This User, but it's there.
Some things can't be disabled, eg the embedded crapware in Google Play Services; Exposure matching, Personal safety, etc. Some things can be temporarily disabled through/DeveloperOptions/RunningServices, but not only will this only last one boot cycle, some services will respawn autonomously - notably Exposure Matching Services.
Making a list of everything disabled is important, especially if taking the scorched earth approach.
With each Android update, I notice reduced control. Many background services and unnecessary system apps increasingly have immutable permissions. And permissions... This seems more convoluted and crippled with every update.
Android is pretty sleazy. But I suppose the bulk of the tech paradigm is too.