It has had… some impact?
Or maybe not.
Youngsters use WhatsApp instead, which is also owned and operated by Facebook.
Which made me wander over to Wikipedia and find this:
Brazil
On December 17, 2015, mobile providers in Brazil were ordered to block WhatsApp for 48 hours. The ban was ordered for the service's failure to cooperate with criminal court orders in July and August 2015. The following morning, however, a judge from the appeals court ordered that the ban be lifted for being an unreasonable response, recommending that the company be fined instead. Following the ban, but prior to its reversal, Facebook CEO
Mark Zuckerberg responded by stating that he was "stunned that our efforts to protect people's data would result in such an extreme decision by a single judge to punish every person in Brazil who uses WhatsApp. We hope the Brazilian courts quickly reverse course." The competing service Telegram reported that 1.5 million Brazilians had downloaded its app while the WhatsApp ban was in place.
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