This has to be one of the least effective and stupidest knee-jerk reactions I've yet seen. It would be more to the point to ban shopping centres imo. Or teenagers. Machetes are really really easy to make - long grass slasher machine blades make the best ones. This is traditional in the bush for clearing scrub and butchering deer/sheep and opening Queensland Blue pumpkins if you can't find the bow saw. Just screw the blade to a handle of some sort and sharpen. And I don't think they're going to ban council grass mowers anytime soon. Or Bunnings. Or pumpkins.
Scythes are a bit different - really thin blade at the end of a long pole. Very specialised for it's purpose - mowing grass really low. A machete is a thickish chunk of metal and quite heavy.