In humans, we don’t usually castrate them because it throws their hormones out of whack, and causes all kinds of issues, but wouldn’t that also be the case for some animals, since their hormones systems are fairly similar?
Why is it that that we remove the testicles entirely, rather than giving them vasectomies like we do for humans?
Until you ask someone with basic knowledge of feline physiology.
…Cats are intentionally promiscuous and can have litters from multiple fathers. It won’t change a thing. Unless you sterilize almost all male cats. Before that it doesn’t change much - and as vasectomies are far more cost intensive you can actually sterilize less of them. So more fertile male cats will stay in the population.
Besides it is actually kind of cruel as a significant portion of non-castrated feral male cats get injured during these fights - so it adds an unnecessary layer of suffering as well.
And of course it makes the males basically unadoptable when they are not castrated and end up in a shelter- males are really really unpleasant pets unless castrated. Better do it right - or even better make sure that people don’t let their pet cats don’t go feral at all. Because even a castrated feral house cat does wrack havoc on the ecosystem.