It’s weird to me that there isn’t a full four paragraph rant in the Wikipedia article about J# - just complaining about how everyone’s first “Hello World” was guaranteed to fail to compile due to bugs in the file rename algorithm.
The usability failures in J# are the stuff of legend.
Compiling to an additional OS, today, can be a pain in the ass.
Compiling to an additional OS, a couple decades ago, was a monumental ongoing never ending pain in the ass.