I think it's still doesn't happend only because precedent like this are bring down the market and destroy the multimillon their investments
in the mining equipment.
Exactly. It's a loophole (which is much, much harder to exploit than you let on, and gets even harder as the system grows) that is pretty much impossible to exploit in practice because it would entail bringing down the whole system, which would hurt the ones bringing it down the most. It's like mass suicide, except without the involvement of cults -- completely and utterly absurd.
Viewed in this light, it's practically impossible to freeze a Bitcoin address, and it's practically impossible for a 51% attack to happen in Bitcoin.