I'm guessing mainstream means that it's enough that traditional finance has had to deal with requests to invest in it to some degree. https://michaelwgreen.subs

I'm guessing mainstream means that it's enough that traditional finance has had to deal with requests to invest in it to some degree. https://michaelwgreen.substack.com/p/do-not-buy-this-etf-1e80ad0d2401 https://michaelwgreen.substack.com/p/do-not-buy-this-etf-1e8... (May 2021, Michael Green of Simplify) sorta touches on this.