First, it is not true that gluten intolerance is easily diagnosed. It is often misdiagnosed or not diagnosed at all.
Second, it is very difficult to avoid wheat or products containing wheat.
It's incredible how much wheat is used in food processing. Shredded cheese is dusted with flower. The majority of soups have wheat ingredients. It is even difficult to find ice cream without wheat added. No more cakes, cookies, brownies, non-frozen breads, etc, etc.
Gluten intolerance sucks.
My autistic grandson was placed on a gluten free diet for a while, thinking that it might help him. It did not, but the year he was on it was pure torture for him and all around him.
My dad has it. It seems more of a battle to avoid products that are high in it. So staying away from breads as much as possible. As you said, the other stuff you can’t do a whole lot about but keeping the amount in the body as low as possible is the best he can do.