Also, it is a lot better for tourists than having horses faint or die on the pavement in front of your kids - which is bound to happen more frequently with the weather becoming warmer.
https://youtu.be/NLxRoDuwaeY London traffic circa 1900
Banning something just because kids 'might' (would love to see a % chance on this) die on the streets is alarmist nonsense. Should we ban trains and cars, too?
There's ways to mitigate cruelty and exploitation, just like we do for humans.
What's the difference between this and people keeping pets couped up indoors and exploiting them as 'emotional support', etc? If animals are meant to be wild and not exploited, people should at least be consistent.
And for what it's worth, even if you provided your animals with the greatest care (which they didn't), just putting them to work for 12 hours a day on a hot paved street was largely seen as abusive.
It might not have happened often that a horse fainted or died on the job, but when it did it caused enough of an uproar to pressure the people in charge to do something. As someone who has witnessed it, you really only want to see that once.
I've lived in the UK, and now Finland, and generally the only time I see horses are when ridden by the police.
(In Scotland it was common-place to see mounted police outside Rugby and Football matches, apparently the increased height gave them good visibilty. I'm sure they trained and selected for even-tempered horses, but I always imagined the combination of thousands of shouting pedestrians and horses was a bad one. If a horse got spooked things would end pretty badly, and quickly.)