I have a park very close by, in constant use daily, not least by dog owners.
Some on leads some not.
It has two fenced off play areas, plus a lot of humans doing their stuff, kite flyers, conker hunters, grass boarders, bike riders (steep hills).
I take my two dogs up there for their exercise. Sam has one of the most benign natures I've ever seen in a dog, unfussed by dogs or humans, if they call him or if dogs approach him he'll go with the flow, if growled at he'll steer clear, so he goes off the lead except when within 50 yards of the gates.
Fry on the other hand, is unpredictable with other dogs except Sam, so he's always on a lead. He's fine with people just other dogs.
Both can be recalled, and I do if they go within 10 yards of kids, because you never know how comfortable the kids are with dogs.
Loose dogs can be a concern with Fry the way he is, but I can't complain because Sam is loose, so it's up to me to be always aware of the situation and stop anything developing.
I've only had one complaint ever and that was rather bizarre, a guy raged at me because his loose dog stuck its nose in Fry's rear unexpectedly from behind me and Fry snapped at the dog. No harm, but he ranted all the same.
We've nearly been run down a couple of times by kids on bikes, and once a Husky/Wolf/Alsation nearly knocked me down but no harm done and it's the park after all.
Everyone has a responsibility to think about what they are doing in the shared area and take reasonable care. If Sam became a pest or a nuisance than I'd have to take more care and put him on a long lead.