It was sold as a way to manage complexity but then made everything complex in a different way. For some problems, OOP makes sense, but for many I think it doesn’t. Unless you have a Rust like trait system that looks a lot like OOP but isn’t. That works well. Essentially don’t put state inside your classes, or you will be spending lots of refactoring time on moving variables up and down in the class hierarchy or throwing computer out of the window because a variable on second thought shouldn’t have been added near class Y.