Every idea seems obvious to add to the OS in hindsight, yet we all lose. For a small shop these apps are their lifeblood and so they get constantly nourished. For a large corporation, this taking candy from babies moment constitutes a blurb in a keynote followed by minimal attention or innovation from then on.

Copyright and patent law were intended to prevent this, but software has no real moat from this. The little plants in the garden get to prove the concept just before the giant redwoods draw all the water from the soil and block the light -- and the legal system is setup to favor this.