ETC isn't even that small of a coin. Relative to bitcoin and eth it is but compared to many others it's big. Why anyone thinking of creating a coin now thinks that POW is the solution is beyond me when there have been numerous examples of the vulnerability it faces. I think in time we'll see most moving away from POW.
The problem is not in the POW but when you are facing the ASIC miners and they will be so easy to get the domination from the blockchain. BTG ever experienced with this thing but after blockcking ASIC and then it's fine.