If cows were raised like they were throughout history - free range instead of in factory farms, and calves sharing closeness and the milk - would you have the same objection to them being slaughtered at some point later without much suffering?
But such a system does not, and probably can not, exist at any significant scale in the modern era. And while instant death is sometimes preferable to a "natural death"—I doubt those interested in "harvesting" the corpse would ever have any incentive to care about whether the death was "without much suffering".
I am. I work really hard to make sure my animals have the best death I can possibly give them. There’s horrific things happening in industrial meat production, no argument. That doesn’t mean that everyone who raises meat animals is uncaring.
A large portion of cows do roam free in pastures in the US.
They are only processed several days before where they are fed a large sum of grain in those crowded cages you see.