That is my understanding too, but many people equate rural life with „natural“. Unfortunately the rural environment is all but natural. The cultural landscape that has been engineered over centuries all but displaced true wilderness and is largely devoid of biodiversity. The better we become at industrial agriculture, the worse the situation is.

That depends on the rural environment. Especially grazing lands, like north European coastal heathlands, may have been managed with controlled burns in between grazing for a thousand years, to the point that they have their own biodiversity, that may get lost if they are disused.

Not everywhere, you are looking at only suburbs vs cities.