Do we need a way to tombstone APIs that have been removed across all versions?

[johanste]

Clear and concise description of the problem

Today, we can indicate that something has been removed in a given API version, but is still supported in earlier versions. However, we do not have a natural way of expressing that a previously existing API has been removed across all API versions short of either a) deleting it from the service description (which also erases all historical traces of said API/generated docs etc.) or b) adding an at-removed for the first API version (which is kind of a lie/incorrect).

Being able to say that something used to exist but has been removed could be helpful for posterity/figuring out how to update code that used to work.

Checklist

• Follow our Code of Conduct
• Read the docs.
• Check that there isn't already an issue that request the same feature to avoid creating a duplicate.