I feel like most of these brand will remain relevant.
The skateshop in my town is super spiteful towards these brands, as the owner believes that these brands are just temporary and trendy. Its unfortunate because for a skateshop, I feel like now is the time to help build up these brands, making it a "win win" for the skateshop and the companies, like FA, 3D, Bianca, CALL ME, Palace, All Timers. Also, keep in mind that these companies, like others, are ran by skateboarders, who are far from reluctant in celebrating diversity and modern ideas. So if anything, their ideas will translate into more superior products and a solid image, thus having a huge backing.
I really do not see these companies going away, as A. its way too early in the game to talk about the end of them, and B. this resurgence of new brands is nothing new, rather the cyclical trend of this crazy universe known as skateboarding.