There is a moral and ethical case for moving beyond meat. Humans are fully capable of surviving without it.
However it remains true that biologically speaking in terms of both our teeth and digestive systems we have evolved as omnivores, both meat and vegetable eaters.
Throughout our existence on this planet we have killed animals to eat them. What the advance of civilisation has done is to divorce most of us from that process, so we experience meat as a pre-packaged commodity on supermarket shelves. Throughout most of prehistory meat and other animal products, eg furs, were essential for our survival but this is no longer true today.
But many of us are of an age where we were raised to eat meat and have always done so. It is not easy to change at my age, and any temptation by anyone to indulge in any self-righteous morally superior lecture in response to this will do nothing but make me did my heels in.
I am not persuaded that eating meat as all our ancestors have done makes me a morally bad person, and anyone who tries to make me feel bad will not win me round but turn me against them. But at the moment I am open to persuasion if it takes an understanding tone.
The change to a wholly vegetarian society is not going to happen overnight but gradually, and the people need to be carried along with it and be on board at every stage.