This black-and-white thinking ignores the spectrum of what constitutes non-toxic. There are those that accept nothing short of perfect purity in air, water and food, a condition which has never existed in a million years of human history. Others are less concerned about humans and more about ecology. Still others value the morals of human-animal relations above issues of nature.
So no, we are not all 'ecologists', not in the same sense anyway. And not to the same degree.
I'm not so sure. No water systems at all. Lack of covered drains. Firewood for heat in any population center. Tuberculosis and cholera. Unrefrigerated meat.
Sure, but on the other hand no large-scale industrial by-products, no islands of plastic in the sea, the mountains of trash were less durable and closer to being biodegradable.
So no, we are not all 'ecologists', not in the same sense anyway. And not to the same degree.