If I decide to instead eat e. G. 1kg of low quality meat every week I am responsible (by eating meat) for an amount x of CO2 emissions.
I don’t think that’s true. those emissions happen regardless of whether you eat it. they happen regardless of whether you buy it.
Source please.
Your analysis undermines genuine science by disregarding the reduction in demand which reduces the supply and forming a data set with a sample of 1.