COBOL is an arcane, baroque and verbose language which serves a very singular purpose in business - processing records. I fail to see how it's "easier to learn" unless all you ever wish to learn in computing is how to process records on mainframe computers.
If you learn computing because you want to write a game, or a website, or an application, or manage a database. i.e. if you learn for the reasons that 99.99% of people learn for then COBOL is unsuitable. Any general purpose language would be more suitable than COBOL for learning. If Java doesn't float your boat then there are the likes of C#, Python, Go, Dart, C++, Ruby etc.
It's hard to see how you think OO has "failed" given that virtually every piece of modern software uses it implicitly or explicitly.