Crypto could be illegalized everywhere and we would still be able to use it, they could have stopped it in 2009 but now it's too late. No matter what we will be able to use and trade crypto.
I would not worry about this.
You apparently haven't read the linked blog.
Cryptocurrencies issued such that they aren't investment securities (such as issued with non-sneaky, fully competitive proof-of-work) are exempt from SEC and FinCEN regulations.
All "ICO-issued" (and that includes obfuscating sneaky mine/burn scams such as Dash, Bytecoin, Byteball, etc) tokens will not function as cryptocurrencies for the reasons stated in the blog.
If you're going to attempt to refute the blog, then please actually refute the points in the blog.
I read the blog, who cares if they aren't investment securities? And there are coins that will still be legal because they didn't have an ico