> it's substantially more work to clean and organize the code for publishing, it will increase the surface for nitpicking and criticism (e.g. coding style, etc).

I should take a couple of hours. The code works? You know how to reproduce what you did, right? It shouldn't be perfect. Shouldn't even pass code review. Should just work.

> many scientists look at code as a competitive advantage so in this case publishing the code will be removing the competitive advantage.

Well depends on the field I guess, but you also want recognition and impact. What is the point of publishing a result no one uses?