As Bitcoin grows in popularity and user adoption increases, if the max block size does not increase then tx fees will inevitability rise. Eventually tx fees will rise enough so that Bitcoin will be prohibitively expensive to use. This is where things like blockstream's Lighting network and Blockstream's side chains come into play, as people will use them as an alternative, which will allow Blockstream to profit, and will cause Bitcoin to be to expensive to use except when used for very large financial transactions (aka only the big players can afford to use Bitcoin).
The above scenario will happen unless the maximum block size is increased in the near future. The best course of action is for the core devs to all support a larger block size that increases over time (to allow for bitcoin adoption to grow over time, and for technology to become more advanced to support larger block sizes). All of the core devs supporting larger block sizes over time will make it so the decision to support this kind of hard fork would be more obvious to the major economic players in the bitcoin economy.
While there is speculation that Bitcoin will become more centralized with a higher block size limit, it is all but certain that Bitcoin will become substantially more centralized with the block size limit remaining unchanged, probably more centralized then what would happen if such speculation would be true.
Does "Fee" work?