You mean fenced dog parks? There are plenty of threads here about how well that works for lots of us...
Though we are extremely lucky in Canberra to have lots of unfenced off leash areas. Every suburb has at least one off leash oval. Surrounded by streets. You want to make sure you have total control over your dog when you let them off there.
We live in a very risk averse society. It's is a real bug bear of mine. Happens with kids too.
Laws like that don't do anything to encourage responsible dog ownership. It's a bit like making everyone drive 25kph because there's people on the road who can't drive. Bring on a licensing system. You need a licence to keep a snake, why not to own a dog?