The Sky Is Falling: Oracle (Might) Want Your Money for Java SE in 2017
dzone.com
dzone.com
But yeah, the OP is a perfect example of a strawman.
Not just windows though afaik, JRocket MC is integral to the oracle JVM.
They say if your app controls some external "hardware", it makes your system embedded. Does sending a command over a serial line to an actuator from a Java app makes it embedded? Apparently yes. How about Bluetooth devices? A joystick? Controlling a router?
Now, how about a rack stuffed with ARM units, are those embedded? They might be quite easily, depending on how Oracle interprets it.
Note well: IANAL. But I think Oracle would have a very hard time forcing payment. "Stop using it, or else pay up" is within their rights, but will still be an incredibly negative PR mess. "Uninstall the part that was supposed to be pay-only, or else pay up" is perfectly reasonable.