Emulsifiers are also being investigated for causing issues like that. I find them to be a more compelling explanation for rising rates of these issues.

A lot of specialty vegan and dairy-free products are filled with them to turn plant-based ingredients creamy or milky. They're also very common in non-specialty processed foods that many vegetarians eat more of than omnivores.

News article: https://www.reuters.com/article/us-science-emulsifiers/study...

The study: https://www.nature.com/articles/nature14232