The reason people can't control dogs around in-season bitches is that they have failed to properly train their dogs.
If they can stop their dog chasing prey whilst on a lead, then they can stop their dog hauling them over a road to follow a bitch - and if they cannot, they should not be walking that dog, they should take it to a secure field or have someone who can control it, walk it.
I walk bitches in season to just before their receptive period (middle of the season ish), we avoid off lead places or narrow paths with no room, and we avoid busy dog walking times of day.
I do use anti-mate spray to try to disguise the scent too!
On top of that... I pick routes that do not involve crossing busy roads wherever possible, doing the best I can NOT to leave a delicious scent trail across a busy road, just in case someones dog is loose.
The idea that it is impossible to train males (and no they don't need to be intact, many neutered males will if permitted, bolt off after an in-season bitch and, if shes willing, can and will mate her!) is just bullshit.
The fact is, people simply haven't bothered and as they rarely come across in-season bitches, its rarely an issue for them - and then when it IS they can trot out the line 'well its impossible to train a male to ignore an in-season bitch'.
FWIW I would neuter a bitch after two/three seasons depending on whether she's small/medium/giant breed, but thats because each season increases the risk of pyometra, not to make the lives of people who can't be arsed to train their dogs easier!