Public hesitation wasn't just about a general dislike of tracking; it was rooted in specific, documented risks:
Users expressed deep distrust toward private tech companies, fearing their sensitive health and location data would be sold or shared for commercial purposes. Privacy Concerns Hindering Digital Contact Tracing
For these apps to be effective, experts estimated they required adoption by approximately of the population. In reality, adoption rates in many countries plateaued well below 30%, with privacy concerns cited as the primary barrier. The Core Privacy Fears Public hesitation wasn't just about a general dislike
Even with anonymized data, researchers warned of "linkage attacks," where hackers or institutions could cross-reference anonymous app data with other public information to re-identify individuals. The Core Privacy Fears Even with anonymized data,
The very nature of a notification—telling you that you were near someone infected—can inadvertently reveal that person's identity in small social or professional circles.
Privacy and Security in Digital Health Contact-Tracing - MDPI