Maybe it's a scale thing. If you are sologeneer working on your own project, with a singular vision, making tools to make your life simpler is a no-brainer.
If you are implementing a feature for stakeholders on a large piece enterprise software, you don't necessarily have knowledge or understanding of helper tools from earlier work, so that's extra overhead to understand anything non-standard. Then when the stakeholders change direction (as they often do), any assumptions in your code may need to be upheld while implementing the next feature.
Edit: This is also why it's nice to use widely adopted libraries and frameworks for any helper code. That way a new starter has a chance of understanding what's going on.
For this to work I think the assumption is that the benefit of gerrymandering is less than the "anyone who doesn't like the in power guys" effect. e.g. % of disgruntled swing voters.