As for food prices: mostly folk are paying for the processing. Eating less food of better quality is healthier for us and for the land- but not for the big corporations who influence all govt policy.
Yes, consider a steak or mince from a cow which spent its whole life eating grass on steep UK hillsides which as you say would not support other food production methods.
Compare that to something from the 'plant based' section of supermarkets, a factory-made product based on soya transported halfway round the planet with a total 10+ other ingredients grown by the aid of factory produced fertilisers and pesticides/herbicides, plus 2, 3 or more factory made chemical additives.
One is the good for the planet (and incidentally whoever consumes it), the other makes the government a lot of money in taxes at every complex stage of production.