I wonder if this can be viewed as (yet another?) example of companies externalizing the negatives. Pollution is the classic example, both during manufacture and at the end of the lifecycle. In this case, it would be financial risk. Founders bootstrap a start-up, either with their own money or outside investors, and these folks carry all the risk. The established players can safely wait until the startup either fails or succeeds, and buy into a sure thing in the latter case.

I think it is simply a consequence of technology enabling instant global communications and decreasing marginal costs precipitously giving bigger players an enormous advantage.

I'm not sure about that. An acquisition is a risky thing for a company to do as well. It's never a sure thing and correctly pricing the acquisition or predicting if the company will be successful with the acquisition is also not guaranteed or easy.

For some highly regulated industries, it's hard to bring small products to market. In banking, there are tiered regulations based on your size (in the U.S.) so there's more overhead for large companies