Definitely a weird thing to highlight as a "surprise" but also not quite right, since it should be exactly half... and also that portion of the pie should be a semicircle (around 180 degrees even if it's 48%)... but it's significantly smaller than that somehow?

It does point out that wage is still and predominantly the biggest factor in net compensation.

This is assuming that bonuses, commissions etc. count as compensation, but not wages.

Net compensation includes bonuses and such. It's not just wages. The 48% figure is the cumulative total of people with net compensation < 30k. So it's not wrong by construction just oddly misleading.

If you look at the SSA data, It also highlights that the mean net compensation is about $48k. And 67.4% of wage earners have net comp below that figure. Which is in line with the graphic.