Well have fun paying massive tax, being put on on some sort of list, and also get some good lawyers. Biggest reason to hold is that even if your bitcoins are from licit origin, it's a gamble how the government will deal about it.
Also lol at this is the last bullrun.
I'm not too worried about the risk in my country, the worst that can happen is to lose the money, and I can live without it. I'm not interested in living in fear.
It's easy to treat lightly my comment about the last bullrun, but when the price hits a low, then a new low, and that lasts for months, it's very depressing. Last time I had only kept enough cash to pay back all my investments, so that I'm now neutral, but for the next time, I definitely want to have cash in hand.