> If everyone could eat locally grown ethically sourced meat, there would be no need for veganism

Vegan = avoiding cruelty, suffering and exploitation as much as possible in a pragmatic way.

Veganism isn't a diet. It's a moral choice that people make, as they don't want to support an industry that's killing our biosphere and inflicting unnecessary cruelty - since in most parts of the world people don't need meat anymore to survive.

So your sentence doesn't really make sense. You'd probably want to replace veganism with 'pure plant-based diet'

Even if you raised a cow yourself - petted it everyday, cared for it, even played with it etc - how is it ethical to kill it to enjoy its flesh - if your survival doesn't depend on it?

Animals just like us don't want to die and they do everything to avoid pain.