Recently, protonmail had been DDoSed. The attackers wanted a ransom (to be paid in bitcoin), and protonmail ended up paying the ransom to stop further attacks on them. You can read about it here.
It seems likely that the people who coordinated this attack also coordinated a DDoS on MEM, Abraxas, Kraken and any other markets that are experiencing downtime. This would make sense since markets have a shitton of bitcoin.
I hope this is the case since this would mean that it's not a government attack or an exit scam, but I dunno.