but many of the current crop will never return money to investors.
I largely agree with you, but the huge investments currently being made will be very hard to get a return on. Token costs will come down, performance will go up, and you want to be in the business of selling the picks & shovels, not doing the mining.
Which is of course why nvidia, google & TSMC are in pretty good positions, but even their valuations have some bubble in them.