I think the point was that since they banned gas leaf blowers, they might as well have banned all leaf blowers, leaving nothing but hand tools. Of course someone could invent a hand-cranked blower or something... would be interesting to see exactly what loopholes in the legal wording people would find.
What? No. There's still electric leaf blowers allowed. They exist and work fine (but are a little more expensive)
Yes, I know. Parent was proposing a hypothetical scenario.
I'd just use air from a motorized large volume air compressor with a long spray attachment. Technically, not a leaf blower. Ahh malicious compliance!