I think I have reasonable grounds to disagree, but I don't want to cause offense or upset, so to be clear I am not attacking you or your thought process, just the conclusions.

There has been a long history of these religious approaches to diet influencing scientific research. If we discount all science done by ideologically biased institutions such as those in this study the actual field looks very different. If we further discount known bad methodologies, for example food frequency questionnaires (FFQs) which are shown to be absolutely inaccurate in most cases, then we again find less support for the conclusion that plant based diets are better for humans than meat based diets. In fact, we will find that there are almost no interventional studies of any length that even potentially could tell us that a meat based diet is worse than a plant based diet.

In most cases the researchers fail the very first step of defining plant based, meat based, high carb, low carb, ketogenic, Mediterranean, and so on. The studies are all way too short, most being done over less than 12 weeks, and very few have any sort of cross over or similar control. Most of the studies are purely observational and have no intervention, so no change can seen as causally linked to an outcome. Most studies are funded in such a way as to bias the outcomes. Most studies are not preregistered. Many suffer from p hacking. Many have no clear outcome measure but instead target a proxy, for example blood cholesterol, but they do not actually look at the true target outcome, heart disease and death.

The whole field of nutritional science is unfortunately very unreliable at this time due to ideological and financial conflicts of interest. This study is a great example. Given that it is well known that FFQs are unreliable why was this study approved at the outset? Why was a further clarification of the actual diets of participants not taken at some point in the study, even from a subset? Why is this type of study funded, executed, and then passed through peer review? If this arrived on my desk I would not approve it for publication simple for methodological reasons. Why does the journal allow a title which is so provocative and clearly useful for pushing an agenda when their supposed scientific credibility are riding on their reputation as gatekeepers of truth?

If we had real science I would be keen to see it. This does not meet that level of quality and the continued publication of this type of unfit paper is dragging down the whole scientific endeavour. If we continue to allow people to claim to know what they cannot show we will end up believing anything and making grave mistakes in our choices about how to live.