Sadly it's not really that simple (speaking as someone who has shipped JUCE apps on iOS and Android) – sure, the code might compile on every platform, but in re

Sadly it's not really that simple (speaking as someone who has shipped JUCE apps on iOS and Android) – sure, the code might compile on every platform, but in reality there are still a bunch of other factors that can make stuff not work, or perform badly, or complicated to test, or whatever. I suspect really it's that companies are not willing to do the testing or support required to say they support Linux.