I've followed this story for years, and there's no new information in this piece. Over a decade, the only association of passenger gear and cockpit trouble is from "at least 10" reports by pilots in the United States, all of which are anecdotal, and, ostensibly, none of which have proven repeatable. If they were repeatable, we'd have different restrictions and rules, instead of ever-fewer ones.
The article notes the study done with the permission of the FAA and airlines that showed there was always at least one cell phone on during a flight, if not more than one. Today, one would guess that dozens of electronics are actively seeking and producing signals in a standby mode.
Occam's Razor would suggest that avionic disruption would be commonplace with the sheer quantity and variety of devices across every plane model currently in operation. This has not occurred. The article doesn't discuss that disconnect between concern, repeatability, and reality.
Lufthansa Brings Back In-Flight Internet