Telegram still has the best UI/UX among messengers and 99% of users care about it. You can't shame normies into using FreeBSD instead of Windows/OSX because it's more secure, just because FreeBSD's UI/UX sucks and webcam does not work. Similarly, only a few people are willing to use Signal just because someone says it's 'more secure'. Don't forget there are a lot of people who make nudes, dick pics, etc and share them publicly on the internet or/and Google drive.