I've always wanted my editor's go-to functionality to take me to an abstract class instead of the place where the actual logic resides. Good times.

Any modern IDE will let you immediately bring up the subclasses with a single hotkey. If you have an abstract class with only a single subclass and that's not because new code is going to be added soon then yes, it's a bad design decision. Fortunately, also easy to fix with good IDEs.

In my last project every class had a corresponding abstract class, and then we used DI to use the real class. Good to be rid of it.