For most part, it can do a lot of things easily, but since it was a heavy language when the computers was as powerful as a Raspberry Pi (MK-I), it became infamous because of its resource usage.
This problem was compounded by Java's "conceal programmer's errors" mentality, especially in Java Swing. Swing has a very specific way of initializing things, and if you mix them up, Swing fixes them internally, but with a performance penalty. This results in performance penalties and increased resource usage.
As a result, Java was used as programmers' MATLAB for a decade or more. This is because it's very widespread, and very hard to monetize. It became a commodity runtime like Python in early 2000s (and Sun was actually happy about it).
B) Not liking Java doesn’t make someone a purist.
C) You can solve business problems in other languages besides Java. It’s a common misconception amongst Java programmers, I know.