Lots of possibilities. Farms are horizontal land users, mechanize the process and we could have vertical structures to create the food. A distillery of sorts. Artificially grow some kind of genetically designed raw product that would yield multiple products. It wouldn't have to be functional, just eat and grow in vats until harvest time. Like fur balls with a meat core. Get wearing apparel and a steak at the same time.
There will be all kinds of foods brewed in vats. A lot of people eat one kind of insect or another but ask anyone if they want to invest in brewing cricket protein and you will only hear crickets chirping. Ask if anyone wants to invest in synthetic red meat and the lines of investors will be endless. There are all kinds of foods that have protein components so it would be easy to substitute synthetic protein for natural protein. Waffles made from algae, what's the difference when synthetic flavors will be added to recreate the original product.
With a population that will easily hit 9 billion people are going to be making food any way it can be made, and eating it. We already eat a lot of prepared foodstuffs that are artificially constructed to make them look and taste the way they do so it is an easy matter to change the ingredients going into manufactured food. It's all already coming out of barrels. All kinds of unnatural substances are used to shape the agricultural products while it is growing. We are just modifying the additives and the framework used to make the food.
I would think most synthetic stuff starts out costing more but goes down as the process is improved. So many synthetic products now, there's no reason food won't be added to the list. It will probably become the food of record for those who can't get enough now. Big markets to experiment on. It's not trendy yet. Seems like most new versions of things nowadays don't get made out of necessity but start out as costly trendy objects whose price starts high but comes down as more people buy into it. Start with the high profit zones where quality counts, then move out to the low profit zones where people won't be able to object to cheap substitutes.
The conversion of consuming raw substances and converting it to meat on the bone inside animals is highly efficient. The animals are eating stuff that is naturally growing, all part of a self sufficient system, but the animals aren't there to be mass killed everyday. Artificially expanding out parts of the natural process doesn't it mean it will remain an efficient process start to finish.
All the meat eater populations are picking off parts of the populations they feed on in very defined ways that do not decimate the populations. If they do decimate the population, the populations will naturally shift to other sources or locations or develop new strategies. All the different animals are working in the natural environment to keep it robust and growing strong. When you replace the entire cycle with a few types of animals and grow them repeatedly in the same place time after time, the land gets tired, kind of like planting the same crop year after year.