You're right, it's reasonable to be dismayed, but imho not so reasonable to want to keep the metrics hidden.
Feels like we, as an industry, already had this conversation in infosec - abot security by obfuscation - which has some parallels here. The conclusion was that hiding things is generally a bad solution to the underlying problems.
This has nothing to do with security by obscurity. There aren't hundreds/thousands of anonymous managers probing into your teams metrics trying to find the single metric that will defeat your team.
