It's not true that all of the gains are captured by investors.
Alphabet's CEO makes about 1000x the average googler, but that's only about 1% of salaries. What I mean is that for every $100 a Googler makes, about $1 goes to the CEO. It's not like top executives are claiming ing most of the value for themselves, the majority of the value a worker generates is returned to them in their compensation.