There is no such thing as truly vegan as we all absorb living beings. True fact.
Fascinating talk by a professor of biology that I can’t completely repeat as I’m not a scientist but something along the lines of tiny bacteria that live in us and get absorbed. Bit sideways thinking but tickled me! 
Ok on the actual topic, Vegans kill animals too, to be vegan you need intensive crop production, this leads to mono cropping and the removal of pasture land and hedgerows etc. As plants don’t provide the same bioavailablr nutrients as animals.
Removing pasturelands and hedgerows and adding in the monocropping issue completely destroys natural wildlife and will quickly kill off our pollinators, without which we all die.
Not to mention the little bugs sprayed off crops and the field creatures swept up in harvesting.
Or the fact that it’s all irrelevant because there is not enough viable landmass to feed a global population on plant based within planetary boundaries.
Add in to that without animal agriculture you have no manure, so will need chemical fertilisers. Good luck not damaging the local wildlife with those!
So to be truly vegan we need to wipe out the majority of the human population (who wants to volunteer their family?), then only grow your own plants, and even then you are going to have to murder a few bugs and snails to stop them eating your plants first.
So. Erm, maybe we let what the farmer do beat continue and allow them to manage the land they understand. Just ensure bad farmers fall outside the law and are prosecuted for any animal welfare breaches?
In that way I am a pragmatic animal lover.