Do you think that other sources give a different impression?

I was reading Wiener's own writings, here and here

which gives the impression of urgency (a sense that he viewed it as a high priority and time-sensitive issue).

Wiener's own writings do not seem to give such an impression of urgency, and I note that he didn't do anything beyond contacting a few union leaders, such as lobbying directly to politicians. Here's how he described his contact with union leaders:

To arrive at this society, we need a good deal of planning and a good deal of struggle, which, if the best comes to the best, may be on the plane of ideas, and otherwise – who knows? I thus felt it my duty to pass on my information and understanding of the position to those who have an active interest in the conditions and the future of labor, that is, to the labor unions. I did manage to make contact with one or two persons high up in the CIO, and from them I received a very intelligent and sympathetic hearing. Further than these individuals, neither I nor any of them was able to go.

Quoting you again:

Capable of what? Some tasks that previously required labor of humans of average intelligence have been automated, and others haven't been automated. There's still an abundance of jobs for people of average intelligence that pay above-minimum wage.

Capable of any job that a human of average intelligence could perform. I thought that's pretty clear from "However, taking the second revolution as accomplished, the average human being of mediocre attainments or less has nothing to sell that it is worth anyone’s money to buy."

The first paragraph that you quote gives the impression that he may have (mistakenly) thought that humans were on the brink of developing robotics that are sufficiently sophisticated to replace physical labor.

It seems clear, at least in his later writings (1960, second link above), that he really was thinking of AGI, not just robotics:

Complete subservience and complete intelligence do not go together. How often in ancient times the clever Greek philosopher slave of a less intelligent Roman slaveholder must have dominated the actions of his master rather than obeyed his wishes! Similarly, if the machines become more and more efficient and operate at a higher and higher psychological level, the catastrophe foreseen by Butler of the dominance of the machine comes nearer and nearer.