I don't know what environments, platforms and coding styles you guys are using, so it's hard for me to picture how you benefit from DI. I'm mostly writing WPF, Xamarin Forms, Blazor Wasm and WebAPI at the moment (luckily no MVC!), and I don't have any problems that DI can solve. I don't have deep class composition problems or "volatile" dependencies or similar where DI would help me.
If I start using some DI container, then I'll have to pick one out of the zoo, learn it, make interfaces and classes, add references, expand constructors, configure it, etc. I've previously found that debugging step-into can get lost in the DI code and the IDE has more trouble finding refences and definitions. Injection code can proliferate and duplicate, I'm not sure of the lifetime of the dependencies, but worst of all it's all just more clutter and something I detest … "magic plumbing". I know some people frown upon this, but I'm quite happy to have a simple static class in the AppDomain that provides services like logging, http client, etc which live for the app lifetime anyway. For unit testing I can just flip a few lines of code. *GK* >
