A lot of is is that modern frameworks include a lot of those behaviors that required you to manually code the patterns back them. e.g., I can create a an Observ

A lot of is is that modern frameworks include a lot of those behaviors that required you to manually code the patterns back them. e.g., I can create a an ObservableCollection in C# with a single line of code, but in 1996 C++ I'd have to go to the trouble of building out an Observer pattern and it still wouldn't have all the features that IObservable does.