Unconstrained on HN Glance

... But if they are higher up the food chain they also accumulate far, far higher levels of heavy metals. This is true for meats and fish.

Where is the evidence that these are higher in nuts and fruit than in meat and dairy?

The article you mention doesn't answer this question. Read harder

Cows are extremely inefficient. How can you say they do an outstanding job? Outstandingly high emission of Methane belching?

This is complete pseudo-science BS.