The proof that there's work remains, though. Maybe taking a block as an example is a bad analogy, because one might mine easier than another sometimes, but the difficulty is a humanly insusceptible parameter that reveals with "certainty" that there's work.

From a quick -getinfo, it's 29897409688833.63. You can't fake that, nor can you drop it by 90%* by any chance, due to the abrupt exposure of average accuracy. There's a specific work devoted, that's publicly known, miners who thrive to finding a valid hash, ASICs in limited supply. The ability for someone who "has not worked for it" to get such vanity address, AKA PoW, is very small, but less than the ability to reward themselves more than it currently has, especially at the time it firstly received coins.

Chances aren't 0%, but it's 100% pointless.

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