Had not heard of Greger, so I did a cursory search. Looks like a mostly legitimate dude with normal human over-enthusiasm for his particular view, but worth a look. Thanks.

"Retired physician Harriet A. Hall, who is known as a skeptic in the medical community,[23][24][25] has written that, while it is well-accepted that it is more healthy to eat a plant-based diet than a typical Western diet, Greger often overstates the known benefits of such a diet as well as the harm caused by eating animal products (for example, in a talk, he claimed that a single meal rich in animal products can "cripple" one's arteries), and he sometimes does not discuss evidence that contradicts his strong claims.[19]"
[en.wikipedia.org]

And...

"While there is some zealotry here, the studies that Dr. Greger enthusiastically talks about are from respected journals and merit our attention. I think his videos are worth watching, but keep in mind that there is some cherry picking of data."
[mcgill.ca]

And...

"What follows is a review of How Not to Die's highlights and hiccups alike -- with the premise that benefiting from the book's strengths requires navigating around its weaknesses. Readers who approach the book as a starting place rather than incontrovertible truth will stand the best chance of doing both."
[healthline.com]