(Assuming you're asking with best intent)

I'm suggesting we stop breeding "livestock" (sentient animals) into existence for a life of torture to then be killed and eaten by humans.

80% of agricultural land is used for animal agriculture. Rewilding most of that land, making some of it habitable, and the remaining converted to plant agriculture would be a far more eco-friendly solution.

What I think you're getting at with

If we stop caring for the cows, they'll die.

(paraphrased)

Which I agree is unethical; however, real world solutions don't happen immediately like that. A slow movement builds, and as demand for meat, dairy, eggs, etc. reduces, the supply will reduce over time until only a small portion of farmed animals remain. They should be cared for in a similar way that elephants on Sanctuaries or rescues are cared for.