Cooldowns won't do anything if it takes wide deployment in order for the problem to be discovered.

If the code just sits there for a week without anyone looking at it, and is then considered cooled down just due to the passage of time, then the cool down hasn't done anything beneficial.

A form of cooldown that could would in terms of mitigating problems would be a gradual rollout. The idea is that the published change is somehow not visible to all downstreams at the same time.

Every downstream consumer declares a delay factor. If your delay factor is 15 days, then you see all new change publications 15 days later. If your delay factor is 0 days, you see everything as it is published, immediately. Risk-averse organizations configure longer delay factors.

This works because the risk-takers get hit with the problem, which then becomes known, protecting the risk-averse from being affected. Bad updates are scrubbed from the queue so those who have not yet received them due to their delay factor wlll not see those updates.