I think this is pure conjecture. I could not find any claim that the CME group actually has any plans to offer any products related to altcoins at all. Why would they even do that? The liquidity of the majority of altcoins (with the exception of maybe ETH) is way too low to be suitable for any sort of derivatives. Additionally, it is very doubtful whether it would be even legal for them to offer any products related to this due to the regulatory uncertainty surrounding most of these cryptocurrencies.
The plan for the futures is centered on Bitcoin and if ever there would be an addition of other coins later I don't think these people are stupid enough to include the so-called scam or shitcoins. Definitely, there can be a big possibility that later on they might include Ethereum and even BitcoinCash but no shitcoins for sure. The fear is unfounded to say the least. let's see how things will transpire under CME's proposal which is not yet approved by the government.