Dependency inversion makes things unit testable.
>testing is good right?
All other things being equal, wouldn't a form of testing that doesn't require rearchitecting your code be better than one that doesn't?
I think you have to weigh up the relative merits of having less code vs. having a lower cost of code change. Furthermore, following YAGNI dictates that you shouldn't really do DI until you actually do need it.
I think doing it to facilitate unit testing is a universally bad approach, and a code smell that indicates that what you really wanted was an integration test.