I've done plenty of maintenance programming. Most OO involves abuse of the paradigm anyway.

Most people don't use inheritance to large AND good effect. Or they use it and create a mess. Deep hierarchies of inheritance need to be carefully designed or they become a mess. All the hiding means less clarity about what is happening when things go wrong.

That said, its a valid approach and can yield useful results. Especially when you can just add a thing to a list and simply call a method on it without having to bother to know what it is.