If you look at my 2018 post “What is the best diet in your opinion?” [repost in 2022], you will find a logic that is simple: your microbiome adapts over generations to the food available. When food choices quickly, issues arise in the microbiome. One known issues:
- “Gut Microbiota: An Important Link between Western Diet and Chronic Diseases” 
- “Effect of ultra-processed diet on gut microbiota and thus its role in neurodegenerative diseases” 
The other day I spotted a non-alcoholic Imperial Pale Ale at Costco and picked up a dozen. During the summer when I am working outside, I like having a cold one when I come inside. Health Canada in 2023 updated their guidance to restrict alcohol use to 2 standard drinks or less per week with discussion about putting health labels (like tobacco labels) on all drinks. This product tastes like a good IPA, but has no significant alcohol — likely close to the common beer that my ancestors had for breakfast, lunch and dinner.
The light went on! Up until around 1900, beer and ales were common daily drinks –including for children. The reason was simple, water was often deadly due to bacteria in it. Clean drinking water was scarce or unreliable. Milk was fine. Coffee and Tea was fine. Water was not. The beer was not the typical 8% alcohol often seen in American Beers, but 2% or less.
This leads to the speculation that removing regular gluten exposure during childhood — via weak beers and plain-old-school porridge (oats, barley etc.) is the cause of the exploding gluten sensitivity!
It is very likely that gluten sensitivity is connected to diet changes – most of our wheat was breed for specific things, like yield per acre — those changes may contribute too. It is impossible to find clear evidence — but blaming drinking water is an amusing suggestion!