Since it's near-universal web deprecation, is it worth learning Java? [on hold]

For a long time, Java was the language to learn if you wanted to learn Object-Oriented programming (a few of my colleagues in my A-Level Computer Science class still swear by it), though these days the language has been deprecated on the web nearly universally.

Since I can write C# (MVC for the web, .NET framework for UWP), is it really worth learning Java: either for web or desktop development?