It's been responsible for a few (security) bugs, and I don't really see the point of it (even more so now we have action=tokens).
I know we don't like breaking changes, which is fine, though, we can either deprecate this and say we'll remove it in X, or jfdi on security grounds
See https://gerrit.wikimedia.org/r/4973 for the latest
Version: unspecified
Severity: enhancement