Quick Response codes, used to share information, could become antiquated before they catch on, with complaints that the codes are too Byzantine for too little reward.
The medical and public health communities have responded to vaccine panics with a wave of studies that refute the concerns, but these studies take time and draw much less attention.
Yeah, it really isn't polite to leave someone hanging. I know it can be hard to say "you're not for me" but that's much better than saying nothing at all!