With so many different ways to access HBO programming, do you think theres still a need for the multiple linear HBO and Cinemax channels?
No. I still believe that the existing library of Cinemax original series will become available as part of the permanent HBO Max on-demand library and that Cinemax will simply cease to exist. (The WSJ, and possibly others, have reported that will be the case, although AT&T has not said.) Maybe Cinemax dies as soon as HBO Max launches or maybe it takes a little while longer, but I don't really see how Cinemax fits into the future of AT&T-owned video services, which will be completely centered around HBO Max. (And, in fact, I think they were likely thinking that this might be Cinemax's fate at the point when they decided on the name HBO Max, which obviously sounds like a combination of HBO and Cinemax.)
But getting to your specific Q about all the various linear channels, nah, as HBO morphs into HBO Max, where the emphasis is on on-demand, I suspect we'll see some of those HBO linear channels die. I think AT&T is already hinting at this with their AT&T TV Now service. It offers both HBO and Cinemax but only carries four of their linear channels: HBO, HBO Family, HBO Latino, and Cinemax. No HBO Signature, HBO Comedy, MoreMax, 5StarMax, etc.
And really, why should they? As we shift to an on-demand world, the linear channels associated with those on-demand libraries really just serve as branding opportunities, curated playlists that allow the company to showcase the content that they're especially proud of at the moment. Those live linear channels encourage sampling by viewers; they're an easy way for viewers to discover new things to watch that they might not have clicked on inside the on-demand library. (How often have you stumbled on a show or movie in a linear channel and gotten sucked into it, even though you had no intention of originally watching?) But there's really no point in having so many of them. If you look at the four channels that AT&T TV Now offers, they're the ones that are the most critical, and differentiated from each other, in defining the HBO and Cinemax brands. If I'm right that Cinemax dies, perhaps the original Cinemax linear channels will simply be renamed to "HBO Cinema" or "HBO Movies" or "HBO Hollywood" and live on as a channel devoted to 24/7 uncut theatrically-released films.