[alt_f4]

Yes, if done perfectly. Then I don't need to second guess it and potentially waste time if the thing removed something important by mistake.

But that's equivalent to solving the halting problem, which is impossible. So, no.

[zizee]

I think if you monitor the code running in prod for a while, it can give you confidence that the code is not used. I am proposing a tool that would help you narrow down logic that is not used, and to automatically create PRs that are manually reviewed/approved i.e. not taking the dev out of the loop.