It is fine to feel confident in your own opinion, but believe it or not, some of those Disers you are disparaging have medical backgrounds. We know what steps need to be taken to correctly identify a food borne illness, and the differential diagnoses that are probable in cases of GI illnesses.
No one is demanding doctors credentials, or donning armor and shields. Simply trying to inform the OP of the normal protocols necessary in cases of actual food borne illness, and the possibility of other sources of his illness. Certainly nothing to be condemned for. I would have posted exactly the same thing if the OP had been visiting anywhere, not just at WDW. The OP posted about his very unfortunate experience. Some of us have attempted to share some of our fact based knowledge in the area, rather than just personal lay opinions.