I looked around and the average salary Q4 last year was over $59k.. I don’t know what the meme used for the “half” metric, but if they used the entire population of the US that would certainly drive the average down by including people of non-working age. The average I cited probably doesn’t account for unemployment, but that’s only 3.7% so that’s not going to push the cited average much lower.
If half the working-age, non-disabled adults in this country were literally only making the meme wage or less it would be incredibly dire.