[BatteryMountain]

In C#'s dependency injector you basically have to choose from 3 lifetimes for a class/service: scoped, transient or singletons.

Scoped & transient lifetimes along with the new GC will make the runtime much leaner.

Some application are singleton heavy or misuse the MemoryCache (or wrap it as a singleton... facepalm) - these will still mess the GC situation up.

If you build web/api project it pays dividends to educate yourself on the 3 life times, how the GC works, how async/await/cancellation tokens/disposables work, how MemoryCache work (and when to go out-of-process / other machine aka Redis), how the built-in mechanisms in aspnet works to cache html outputs etc. A lot of developers just wing it and then wonder why they have memory issues.

And for for the dinosaurs: yes we can use the dependency injector in Windows Form, WPF, Console Apps and so on - those packages aren't limited to web projects alone.