We all know that there is a hard limit to the number of bitcoins that could ever be minted. That limit is almost 21 million BTC (minus a few Satoshis). Long term holders hope that this limit will cause the values of their coins to go up considerably due to increasing demand.
However, there is no limit to the number of shit coins that can be invented. In fact the ETH shit coin now has a market cap that is of the same order of magnitude as BTC. Furthermore it is an inflationary coin.
If many people move their capital to these alts won't this negate the benefits of the 21 million BTC limit for Bitcoin holders?
I think it all depends how similar they are to Bitcoin. But altcoin, such as Bitcoin Cash (BCC), probably will dilute BTC's value if it does make it. Granted that the original BTC has already established its popularity and acceptancy, but some capital will be moved into BCC and leave BTC with less investment.
Other purpose cryptos such as ETH, also has that "diluting" effect, but would not be as significant.
If you believe that all cryptos are competitors and, to a more or less degree, subsititutes, then they will "take" investment money away from BTC.
Just my 2-cent.