I wouldn't really say that I am a big Bitcoin Cash supporter. I have already sold all of my BCH/BCC that I acquired after the split. However I think that the fork of Bitcoin serves as a good example that cryptocurrency allows people to have the kind of currency that want rather than what is forced upon them. Anyone with enough programming knowledge can really make a fork of any open-source cryptocurrency that they want. I would say that the only real issue with making a cryptocurrency successful is getting people to accept a currency as having value.
I think that this is something that will contribute to the fall of fiat currencies. Although neither cryptocurrencies or fiat currencies are really backed by any physical asset (precious metals for example), cryptocurrencies would seem to be more valuable to me than fiat currencies because their value is given by those who use and hold the currency rather than some other organization forcing users to find it valuable. This is the case with Bitcoin Cash. The people who are wanting to use Bitcoin Cash are essentially voting that Bitcoin Cash should be a legitimate and usable currency. However, they cannot force this upon anyone else who doesn't see things the way they do.
Will Bitcoin Cash be successful? I don't think anybody really knows for sure. If you think it is, you are free to choose for yourself by purchasing/holding it. However, I don't think that its success or failure will have a long-lasting impact on the cryptocurrency community. I think that Governments have the bigger problem in trying to get their citizens to see fiat currencies as being valuable.