True -- trans fat is 5-10% of beef fat [1] BUT "a lot" is not the standard when it comes to trans fat. The NEJM article makes the point that trans fat is damaging even in small quantities, like a single gram. It was a great day when trans fat was required to be listed on the Nutrition Facts Label. It spurred snack manufacturers to get it (mostly) out of their products.

[1] https://pubmed.ncbi.nlm.nih.gov/6356151/