Eating synthetic meat won't lower emissions that much.

>Meat and dairy specifically accounts for around 14.5% of global greenhouse gas emissions, according to the UN's Food and Agricultural Organization (FAO).

You can't get more than 14% total drop from synthetic meat or realistically even come close since it still has a carbon footprint and mass adoptions obviously won't happen to anywhere near 100% by 2030.

You're looking a few percent in global emissions drop at most, maybe enough to offset growth, maybe not, but not enough to take a big chunk out of the problem... sorry.

The greenhouse gasses mostly come from burning fuels for power plants, cars and heating. Much of the 'industrial' greenhouse gas is just factories heating stuff up in industrial furnaces, so just another form of greenhouse gas from fossil fuel energy.

Around 70-80% of all human made greenhouse emissions are just from energy in one format or another.. so that's the only places where you will see big drops from big changes.