It was always very easy, just package the JRE with the application, use an installer like any other desktop application, or buy one of those commercial AOT compilers available since the start of century.
But that takes a lot of space
You could not fit it on a floppy
I think it's mainly the fact that it has always been very difficult to create executable files.
Running java requires you to install the given version of JRE instead of just downloading an application and starting it.