Rabbiofberlin, thank you for the compliment.
As far as your second point, I will make the precise point I was trying to make about fruits and vegetable; when the metzius changes, the halacha must be evaluated anew. When new infestation is discovered, the old methods of inspection and washing may become irrelevant, and possibly, when an item recently becomes commonly eaten, the old status of “shelo k’derech achilah” changes.
The halacha didn’t change, nor did our approach to halacha change; its application to a particular item changed.