Why does GERD actually exist it just makes everything annoying

You eat a certain food? Your throat burns
You eat too much? Your throat burns
You drink certain things? Your throat burns
You lay down? Your throat burns
You exist? Your throat burns

This thing is so stupid and for what? If youre unlucky you can get some really crappy damage.
Its such a stupid disease, shouldnt be a thing
Thats a fact.