There are large code bases in production that are productive: Everything that is open source - and still the process isn't as shit as op describes.
So this has to do with corporate hierarchies and not the quality of the code.
Yes there are but these are not without rules. Try to add a new feature to a large open source project as a new contributor. That has probably as much chance of succeeding as doing this in an enterprise.
There is a reason larger OSS projects have the "good first contribution" section. These are small bug fixes where the work is already spelled out typically. You do these to get familiar with the codebase and learn how to make a valuable contribution the size of a feature.