it really depends on a person's reasons for being a vegan/vegetarian.
Many people do it for health reasons - there may be no change for this population.
Some do it, for, as you say, sustainability reasons. I would think this would very much address these concerns. Factory farming is incredibly damaging to the environment - manure disposal systems are inadequate, unsuccessful, are so unholy as to have produced exploding pig shit foam, and are generally environmental ticking time bombs (they leak). Factory farmed animals consume huge quantities of crops, most of which are lost to excretion. The same area of land or volume of crops can feed many more people when consumed directly (vegans/vegetarians) than can be fed when strained through a pig or cow. Meat in a test tube is unlikely to require constant feeding... Even the fossil fuels used for transportation of factory farmed products, as you hint at, should be cut down. Because the geographical constraints on a lab are not the same as the constraints on where you can set up a factory farm.
People who are vegan/vegetarian for fashionable reasons - you know, the truth is that I thought lots of those existed, but since I've gone vegetarian, I don't think I've met a one. If they do exist, I generally just am glad they are eating that way, and move along.
I think a huge percentage of vegans and vegetarians have a more straightforward goal: the attempt to not contribute to animal suffering.
And what I see described - now depending on how it plays out - really seems like something that would entirely, or almost entirely, cut out animal suffering. It's not that there are animal products involved that many of us object to. It's the suffering that the animals involved would have gone through to feed us. I pointed out in another post what a stunning percentage of the pig (around 70%), cow (around 80%), and chicken (a few more players, but among those ten, 75%) markets are dominated by a few factory farming players. You eat those things, by and large, you're eating cruelty.
So what I'm getting at here is that for people like myself, definitions are the last damn thing I am concerned with. Nothing suffered and not a single animal was killed for this meal? Let's eat. Animals stuck in intolerable conditions that you and I couldn't handle for even a few hours, killed in a terrifying, inhumane manner, living in filthy conditions, producing a dangerous product - no thank you.
I hope that gives you some perspective. I'm by no means an expert, having only been a vegetarian for 3 plus years. But yes, I think if this worked out well, it could be very promising.
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