Is there any reason that Tumblr couldn't take the freemium route? It has high engagement, and a passionate audience that might well be willing to pay to keep th

Is there any reason that Tumblr couldn't take the freemium route? It has high engagement, and a passionate audience that might well be willing to pay to keep the same Tumblr they always had, as opposed to a sanitised ad-friendly one. Of course, there's the possibility that its audience won't have the means to pay up, or that people will just go elsewhere.