1) you'd be surprised at how many things are illegal to say somewhere. Sure, malaysia can mame its own twitter, and so can india, and the EU, and russia, and china, and japan, and soon you only have a costumer base in the united states.
2) okay. Do that. Make a platform that stops at 3). Get sued despite fair use (you have a case, but do you have sony money to defend it in court? If you fail, you are now responsible for the legal precedent that memes aren't fair use). Allow people to say the n-word and see how quickly you'll get dropped by advertisers who think having an ad next to a tweet asking for racial genocide is maybe not exactly good brand image.
3) spam is a considerable part of user experience. If every second tweet on your timeline is spam, users aren't going to block and move on, they're going to stop using twitter. Your antispam is not flawless.
It's hard because "block things that are illegal by law and leave the rest" is unfathomably hard to follow for a human, let alone an automated system.
2) okay. Do that. Make a platform that stops at 3). Get sued despite fair use (you have a case, but do you have sony money to defend it in court? If you fail, you are now responsible for the legal precedent that memes aren't fair use). Allow people to say the n-word and see how quickly you'll get dropped by advertisers who think having an ad next to a tweet asking for racial genocide is maybe not exactly good brand image.
3) spam is a considerable part of user experience. If every second tweet on your timeline is spam, users aren't going to block and move on, they're going to stop using twitter. Your antispam is not flawless.
It's hard because "block things that are illegal by law and leave the rest" is unfathomably hard to follow for a human, let alone an automated system.