All these businesses looked incredibly unsustainable for a long time. Uber was a cash shredder. Amazon didn't turn a profit for years, IIRC. They became profitable essentially by becoming quasi-monopolies.

Indeed, LLM companies likely turn operating profits, but I'm not sure that alone justifies their valuations. It's one thing to make money, it's another to make a return for investors.

And sure, valuations are growing faster than you can blink. Time will show if this in turn is justifiable or a bubble.

Cannot speak for the rest, but the whole “Amazon didn’t turn a profit for years” (as an argument about their profitability now coming solely through quasi-monololy routes) is incredibly misleading and bordering on disingenuous.

Since before AWS was even a thing, Amazon was already turning up great revenue and could’ve easily just stopped expanding and investing into the company growth, and they would be profitable easily. Instead, Amazon decided to reinvest all their potential profits into growth/expansion (with the favorable tax treatment on top) at the expense of keeping the cash profits. At any given point, Amazon could’ve stopped reinvesting all potential profits into their growth, and they would be instantly profitable.

This is not the same as Uber, which ran their core service operations at a net loss (and was only cheap due to their investors eating the difference and hoping that Uber will eventually figure out how to not lose money on operating their core service).