I worry that our focus on disruptive ideas is hurting entrepreneurship.

I agree wholeheartedly. Too many talented people are on the sidelines waiting for the perfect idea. Jump in! You can make a very goood living with a good idea, and that positions you well to find a better idea.

The key is to provide value to someone. Once you have a business going, and have a good reputation, then you can start paring down your opportunities and focus on the more lucrative options, or focus on the breakthrough "big idea".