Earlier quoted context omitted.
I agree mostly. Any Java application which does not need GUI other than web is just fine in most use cases.
UIs though... I haven't worked with a single Java based GUI application that did feel smooth, fast and efficient. I wonder why that is.
Additionally Swing has bad defaults, so it requires effort to make the required set of calls to make them look better.
Back in the Sun glory days, there were Sun blogs like Filthy Rich Clients, which lead eventually to a book http://filthyrichclients.org/.
It was a consequence of Sun not getting what it means developing GUIs for the consumer systems, think that their Solaris UIs (SunView, OpenWindows, CDE) weren't that great in that area.
So most Java developers stick with the defaults and as such the majority of Java based applications send the wrong message.