HBO Max is just their newly renamed HBO Go and Now unification. If you had either Go or Now before, you now have Max. It's not really that complicated.
Actually you are incorrect, HBO Go and Now still exist as separate products. It is complicated for people that already have trouble tracking where their shows are on several different services. Even if they intend to merge Now into Max completely which likely is the case they still are making it confusing as hell for the common user.
I'm not sure that confusion will really exist, or that it would be warranted if it did. At least for HBO Now, the existing Android app updated and is now named HBO Max. I just logged into Max using my Now credentials, and it seems to have all the content from Now, plus some extra stuff. I think Max is just a renamed superset of Go/Now (which were basically just two names for the same thing anyway). There seems to be no reason to use Now anymore, and Go seems to only exist as a separate site to appease cable companies that HBO isn't offering a competing streaming service vs what they're giving "for free" to HBO cable subscribers.
