The best defense is a good offense. I express concern about your project's use of Google Analytics and then releasing that data to the public, then about the culture of deletion; and I am criticized for my "lack of research". Sorry I touched a nerve; but all of these issues are decisions that are being made, to not expect critiques of your decisions is naive.
Anyways. Having done my research:
> You don't see that text but instead text indicating the formula has been deleted.
If, and only if, you know the exact name of the package. If you do a search, you get the "no formula found". If you attempt to use the braumeister.org web site, it also will not show up unless you explicitly craft the recipe URL.
> They will be preserved in the Git history for as long as we continue to use Git.
How does one go back into git history and revive deleted formula, given how automated the entire process is around ensuring the most recent version of brew is always in use? By your "deleted" help docs, I infer that it comes down to creating your own cask?
The one example I came across quickly is "abi_compliance_checker'. It was deleted because it requires GCC 4.7. Yet Homebrew is still quite capable of installing and using gcc@4.7. Not that it was broken in a recent build. Not that it was a major maintenance burden - the updates for years consisted of version updates.
This isn't something I need, but it's a great (and quickly found) example of seemingly arbitrary deletion of an otherwise active project.