The problem there is that the only effort that’s rewarded under the wage system is that which occurs in a job. A lot of creative work, care work, community work, and other socially-valuable work goes unrewarded, yet lobbying for tax loopholes or weaker pollution standards, facilitating the burning of fossil fuels, promoting the mass use of pesticides are all rewarded. I’m not not convinced the wage system does reward effort effectively, and there’s no easy way to pull a lot of that socially-valuable yet unremunerated work into it.
In addition, as work is further automated, there will be less opportunity for people to work and be rewarded through the wage system. Does that mean people should stop making an effort until they find some other way to be paid for the things they want to do?
The retention of a class system will simply place the wealthy and those who can hold on to the few unautomated jobs that remain at the top of the pyramid, while those who work in ways that don’t provide them with an income will be at the bottom, even if in some instances they’ll actually be making a more important social contribution than those receiving a wage.