if you have money in a shit "decentralized system", would you prefer to lose all your funds or accepting that someone can stop the tradings and returning your funds back ?

Subjective bias is invalid in this argument. In other words, ETH is not decentralized. The hacker is the lesser evil here.
Bitcoin is also not decentralized. G.Maxwell and Blockstream own it by way of consent from some skinny feeble Chinese miners who amassed way too much power in one place. Bitcoin is even more fucked that ETH. At least ETH has a cooperating team building great shit. Bitcoin has awesome in-fighting and zero progress over about two years.