I agree that environmental costs of beef production are quite high.
For me, personally, what also matters is the relative ranking of impacts. I did some research into this and here are the top personal contributors to GHG emissions (presumably for a person living in a developed country).
(All figures in tons CO2 per year)
Have one fewer child: 58.6
Live car free: 2.4
One less transatlantic flight: 1.6
Buy green energy: 1.47
EV to car free: 1.15
Plant-based diet: 0.82
etc...
The interesting thing is that based on this analysis, on average our transportation usage far dominates the plant-based diet aspect.
Popular press (with some interesting follow-on thoughts about how most of the emissions are produced by the wealthy).
https://www.vox.com/energy-and-environment/2017/7/14/1596354...
original paper here:
https://iopscience.iop.org/article/10.1088/1748-9326/aa7541/...