A good takeaway is to separate different domains for different purposes.
I had prior been tossing up the pros/cons of this (such as teaching the user to accept millions of arbitrary TLDs as official), but I think this article (and other considerations) have solidified it for me.
For example
www.contoso.com (public)
www.contoso.blog (public with user comments)
contoso.net (internal)
staging.contoso.dev (dev/zero trust endpoints)
raging-lemur-a012afb4.contoso.build (snapshots)
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