[egonelbre]

One programmer can make an impact to a degree. Yes, making an enterprise system for some industry requires a ton of coding for business rules. But it might be possible to make that coding simpler/easier so that people with domain knowledge could express it without having to code it, of course this is easier said than done.

Also taking a step back and seeing how things could work differently is a nice idea. One of the most recent examples is Bret Victor, just his demos gave a rise to a lot of new cool stuff. Or take LightTable, it has quite interesting ideas for interactive programming.

Regarding start-ups, take for example TransferWise, it solved a business problem, and it started as a two man band. ZeroTurnaround with it's JRebel, solved a technical problem, but was conceived by one person.

So, yes, one person can make an impact, but it takes solving unsolved problems or noticing problems needing to be solved. Of course one person usually can't be a business, which is somewhat different from making an impact.

As a start I would suggest watching Alan Kay and Bret Victor videos.