There's just not enough money in there for the US techies level of grift they are accustomed to in working for near-monopoly behemoths like Apple/Google.
Especially in a non-zero interest rate environment, putting money into these companies is essentially financing the upper-middle-class lifestyle of tech workers. The only way this appeals to you as an investor is if you think you can sell this kind of business to a company like Softbank, while somehow hand-waving the huge inevitable losses.