Yeah, that doesn't make sense. I dont know how Grantland was doing financially, but its unrelated to cable. In fact, things like Grantland could be viewed as diversifying away from reliance on cable viewers.
Where do you imagine their financing came from?
ESPN just did a round a big layoffs last week and dropping TV revenue was a big reason for that. Grantland was never really expected to turn a big profit and was always the concept car of ESPN's journalism enterprise. It was about branding, prestige, and "doing good work" and was never about money. But when it comes time to lay people off and cut costs, it is hard to justify keeping a project that will continue losing money for the foreseeable future.