Earlier quoted context omitted.
Well the two--building for power users vs for a general audience--often work against each other. And trying to satisfy every audience at once is a good way to satisfy none. You don't want your app to be a Jack of all trades; focus is really valuable.
Do you have an example of how supporting a keyboard shortcut for every action could be bad for a general audience?
I think this is a bad reason. Even MS Office has made this work. But I've seen people act on this type of argument. If nothing else, it should be possible to have a settings menu where you can define your own. Even if no shortcuts are set by default and they aren't shown anywhere else in the UI, it will still be possible for a power user to make the best use of the program.