You're ignoring the fact that it dramatically raises the risk in the venture. When you only have a limited time to profit the risk that you won't profit skyrockets.

It'd likely affect funding at every level as investors realize quickly the dramatically increased risk. Who wants to invest in a company that will be out-competed in two years?

It would likely drive a lot of players out of those markets, bigger players who naturally move more slowly with their conservative product development cycles.

Not that any of that is explicitly bad, but it's certainly a big change.