> for LLMs, because in practice floating point inaccuracies (in particular after exponentiation) prevent values from being exactly equal.

In one thinking trace of 10k tokens, with fp16 or bf16 logits, I don't reckon a collision is rare? There are only 65k floating point numbers with that accuracy. And an agent can quickly rake up 100k tokens, so while not every token will have such a collision of equiprobable logits, it is not rare.