Most of Google's value is the moat they've built around the things that bring in money... their advertising market, google play store, vertical integration, etc

Most of Google's value is the moat they've built around the things that bring in money... their advertising market, google play store, vertical integration, etc. See also Doctorow's Chokepoint Capitalism. Building even a tiny fraction of those moats is mind-bogglingly difficult. Building a third of that moat is insanely hard. To claim that the AI industry's "expected endgame moat size" is one-third of Google's current moat is a ludicrous prediction. You'd be better off playing the lottery than making that bet. I would be happy to bet against this if I could do it without making a Keynes-wager (that I can remain solvent longer than markets remain irrational), but I see no way to do so. Put options expire, futures can be force-liquidated by margin calls, and short sales have unlimited downside risk.