Actually we select for both depending on the line of the stock and have been doing so for a rather long time. You do lose the animal after killing it of course but we have a huge amount data from cattle breeding charts that lets a branch be trimmed if there's some fault with it that will damage the genetic tree.

You can’t use the lens of modern agriculture and data collection to look at the birth and growth of animal husbandry.

We have enough now that the conversation isn’t about if we can afford to eat our cows but how fast we can eat them. The top of this thread was discussing how we got into milk harvesting so broadly when so few have the genes for it. It was more efficient for people handing down knowledge through oral tradition.

I can't decide whether that first para is satire or not