> Only 1 of the original companies of the Dow Jones is still in it today

Small companies become bigger, driving returns. That's why you don't just buy the DJIA but rather index the whole market. Of course there will be turnover - the point isn't to lock into any one stock - don't look for the needle, buy the haystack (i.e. a broader-market index).

If you want to include crypto in the haystack, sure, fine, whatever, but at market weights, it's going to be a very small portion of the investable market of stocks, bonds, cash and other asset classes. At some point, it's enough to just keep it simple and broad. A fraction of percent of this or that won't make or break a diversified portfolio.