While I agree with you that new investors coming into the space helped prop up Bitcoin and prevent losses, I would argue that a lot of Bitcoin's new found value is coming directly from Bitcoin Cash and the hype around it.

You can argue all day long, but in the end Bitcoin Cash created money out of thin air. The lost mining power in Bitcoin has already been replaced on day 1 (for the most part) by mass mining operations that have been preparing for this day for months and anticipated the split.

I know many of my friends sold all the BCC they got for a huge profit at over $600 and just bought more BTC and ETH with their profits. In most of these cases IT IS free money because the other coins are not effected by it and the entire cryptocurrence market cap grew by over $30 billion in a matter of days because of all this hype and the air drop of BCC!