“By contrast, Signal wasn’t even in the top 1,000 apps in the UK on 6 January, yet by 9 January it was the most downloaded app in the country.”
Signal went from outside the UK top 1,000 to number one in three days. It added 7.5 million users in three weeks, and Telegram added 25 million. Network effects only protect you until people believe you’re spying on them. Facebook spent years building the moat and one terms update drained it.