when most of us were doing the same when we received our free forked coins 
The only good use for all the bitcoin forks. Bitcoin Cash, Bitcoin Diamond, Bitcoin Gold, Bitcoin Private, Bitcore, (did I miss any out?) were all at their highest price in terms of real Bitcoin immediately after forking, and all have done the exact same thing - slowly lose value, with the odd pump-and-dump here and there to keep the sheep interested.I'm glad I dumped all that trash ASAP, and increased by bitcoin holdings in the process.
Dumping ASAP isn't the right speculative play, you would have made some nice money if you held BCH during that mega pump. Don't forget that bitcoin has also slowly lost value ( down over 80%)
Bitmain will be just fine, they are still the dominant player in this space. As for Jihan, I'm sure he has a ton of money stashed away, he will be ok.