I understand the sentiment. I love animals and nature too, and I don't like the destruction of life in general (unless absolutely necessary), and that's before we even consider whether something is intelligent or not. Like, I wouldn't even step on flowers, and those are not sentient in the first place.

However, humanity at large needs to consume animal flesh in order to survive. If we were to rely solely on plants, we'd devour enough of them in such a short amount of time that it would start causing mass extinctions - an outcome far worse than continuing to consume animals in a more controlled and less dramatic fashion.

So until we can mass-produce high-quality and healthy-to-consume 3D-printed meat* at a large-enough scale to fulfill the needs of the entire human race, forget about surviving without having to farm and slay animals en masse. (* Or, you can say, any adequate alternative. But let's face it, there is no adequate alternative to meat; it's an integral part of the cuisine of probably every people on the planet, and will probably always remain so. So realistically speaking, the only way to persuade the large bulk of humanity away from eating animals is by giving them the exact same product, but via a different process.)

That said, it's a given that if we have to farm animals, then we must treat them in a way as humane as possible; never cause them any kind of unnecessary suffering while they are still alive. IMO it's more productive to advocate for this more immediate problem of minimizing animal suffering instead of trying to force a premature complete elimination of animal farming, as the latter requires a huge and decades-long transformation of the global economy, possibly with political hurdles along the path. (e.g. See how we're struggling to reduce our fossil fuel usage because fossil fuel companies are greedy assholes and can totally buy government decisions?)

So, for the time being, what I think is a good thing to do is boycotting meat producers who are known to mistreat their animals and getting your meat from other sources like local farms and whatnot; pushing for stronger government regulation of animal farming, treatment and meat production; and working on economically viable mass production of quality and safe 3d-printed meat.

Of course, if you individually decide to go with a completely vegan diet, I won't prevent you; it's your life and you're free to live it however you want. But realistically speaking, it's not a viable option for humanity at large, and not even a desirable option for a whole damn lot of them as well - myself included.