Gab was started when Twitter began cracking down on speech during the campaign. The 'racist' charge comes from their steadfastly refusing to control its users through 'terms of service' other than posting illegal activity. Beyond that... anything goes.

To the Left and the forces of control, that's 'racist' and a harbor for 'hate-speech' It may not be to everyone's taste, but it is what Twitter purported to be and most definitely is not.

That Gab is moving to a crypto-based tipping system a la steemit that means they are dead serious about their committment to the free flow of ideas no matter how distasteful.