Lake Argyle in a mad max desert like climate with no water - Northern Australia

Just created a thread about why do people call Australia’s mostly semi arid floodplain landscape a desert and for some reason (maybe cos I’m new) reddit won’t allow me to reply on my own thread. I had people telling me it’s mostly desert even though I know what I saw on my road trip and it was mostly scrubland, savanna and dry forests. I even uploaded a pic of Australia with trees, greenery and a river and they replied “yep that’s a desert”, was giving me an aneurism tbh I swear they’re joking, can’t be serious.

I’ve got another one, if Australia is mostly desert and the north is devoid of water and life, can someone explain to me Lake Argyle?

I’d like to see people’s responses on this one 🤣

no water, no rainfall, desert yet there’s Lake Argyle? how’d we fill it up? Did we ship the water from Indonesia cos as reddit has said, the north and MOST of Aus is devoid of water and one massive desert? how did we fill it up? and what’s all those other rivers near the ord river and lake argyle? reddit said no rivers just desert, what’s going on?

Please explain, I’ll wait 🤣