I am one of those who has a mild reaction to MSG, my neck breaks out in a flush, and I get a salt type taste for some time after the food is eaten. My girlfriend noticed this during breakfast one day and asked me what it was and I told her "Chalot" (MSG), her eye widened, she promptly left the table and went over to the lady who cooked my breakfast most mornings and had a "discussion", no more MSG in my meals after that. It is a mild reaction and I was not fussed, as I saw it this was part of living in Thailand and eating as the locals do.
MSG doesn't do anything for me. Good or bad. I have a brother-in-law who has avoided it for 30 or more years.
Despite the fact that there is no research to support the negative effects, there are many who swear differently, as you do.
There are far too many chemicals in our food from field to table.