Then i realised the whales don't care about mining cost. They aren't miners, they are whales, and all they care is that this BTC is something that they can manipulate and make a killing.
So, why would they care? You don't mine? Someone else would.
I'm quite certain that whales do actually care about the mining aspect, because less profitability for miners will lead to a drop in hash rate, and that isn't a positive sign in the end, especially if the mainstream media jumps on it as well. It's completely in their favor to not entirely mess with the market like they don't care. If they dump the market down too far, even if it's manipulation, they risk having a bigger whale buy the market up and directly outrule them, and they risk ruining their own game.
Whales rather play safe within a range they consider fair and doesn't work against the ecosystem too much. They are money hungry, but not stupid.
Retail traders on the other hand don't care about anything. If they have to sell far below miner cost they will do without hesitation. As long as they aren't dumping in large numbers, which they haven't been doing much this year, then there is nothing really to worry about. Let whales do their thing, their actions are calculated and smart.