It for sure will evolve and maybe it will go faster than we think!
I am in a position that I don't have to depend in the steem income. So for me it is obvious I will power up as much as I can. All earning, Steem of SBD, are instantly converted into Steem Power.
The only 2 reasons, for me, not to do this is that I need some Steem at hand each week because I do sponsor a contest each week with an SBI share. The other reason is that I need to save at least 40 SBD to sponsor my own World cup contest!
But both I do see as an investment in my Steem future!
Hard work now, will pay off later!
So yes you are right. The ones who depend on a Steem income, should also try to invest something back into the system. Day by day it will be harder to get noticed, to get upvotes and so on. And this will become even harder when loads of new users will enter the system! Each SP counts then! The advantage we will have be creating content of curating content now, will be extremely important!