well java on the desktop and java in the browser are two entirely different beasts. the problem here is not java but the changes that have been made in the browser.

We do have some very old and likely lost all sources "client apps" that are a single JAR and date from around 2003-2004, written in Swing. They still work.

Of course when they stop working they will be phased out, but we have been expecting their death for years now and not happening yet.