What would be the best alternative ?
From a business standpoint, yes I agree. However there are alternatives to hosting your app on the appstore. Third party apps are also available to download on the web. Make it available like that, you would still have your platform without axing people who have been on there for years.
Forget porn for a second and consider the thousands of artists who draw sexual imagery or the thousands of photographers who's shots contain male or female nudity.
Making the app available on a third party basis would protect those users and simultaneously be setting a standard for free speech.
They could have even taken the position of allowing the app to be removed as everyone has a browser on their phones any way. They could access their accs through their browsers, the app just streamlined the process.
This is going to work against them in the long run for sure.
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