That's the Kellerberrin B&S, I think: https://en.wikipedia.org/wiki/Bachelor_and_Spinster_Ball. Hence why the uploader called it a BnS, the girl at the start says "welcome to the blokes and skanks ball", everyone's driving a ute with a sick bullbar instead of mum's station wagon, and they look like they're all fucked up on Bundy and coke instead of MDMA and coke.
Strictly speaking it's a West Australian Inseminator's Ball (as titled) which were for a while run in parallel with the B&S balls although to the best of my knowledge they've both died down in popularity - Muresk Agricultural College very nearly closed, although it's gotten fresh grant money in recent years which may have changed things up a bit.
It shares a bit of overlap with many other variations of a bush party that I've been to, they've all been a little bit unique, a little bit the same.
There's even been a odd local lesser version of the more famous US Burning Man here - inspired by is perhaps the best description: https://blazingswan.com.au/ and not like a B&S, a bush doof, nor a Burning Man.
None of these things look like an inner city warehouse rave or nightclub either.
Note: Burning car and local farm fire truck to stop fire spreading.