Mirrors are not entirely passive objects. Tinting, fog, and scratches affect the quality of their reflection. They can be tilted and turned to reflect a different angle of ourselves or another object entirely. Depending on their shape, they can present a near-perfect image, a distorted view, or they can focus light into a destructive point of intense energy.
There's a bit more nuance to the research which is lost in the alarmist media reporting, but welcome to the realisation that a highly technical field will be misreported on by sensationalist headlines for clicks.
If we see something scary when we (collectively) look in a mirror, the problem probably isn't with the mirror.