Note that the the Java plugin and webstart was removed a long time ago.
I personally regret that the API was removed as it's a few classes and they are still used. Just search JApplet on Github. It's also possible to run applets in the modern browsers with WASM or in Java IDE's as plugin.
I can't answer for the File Pilot author but I've spent many years on writing a file manager.
* It's fun to write and to use. It's like craftmanship.
* Hopefully some companies/people will realize how many hours they waste using the default OS file manager
* It's less risky than developing a game full time (I think)
* Sure, I lost a lot of money to not having a normal job but my bills are low and my priority is more happiness
Better than asking what the money is for, even if the customer gives a reason like "buying a car", warn the customer that if someone on the phone or is unknown at your door asked you to do it urgently it's probably a scam even it they say they are from your bank/company/authorities.
I personally regret that the API was removed as it's a few classes and they are still used. Just search JApplet on Github. It's also possible to run applets in the modern browsers with WASM or in Java IDE's as plugin.