because robots are still 10x cheaper than the low wage workers (in developed countries at least), and low wage worker jobs are usually easier to automate.
They don't actually have 1 billion dollars tho, they have stocks with an estimated value of 1 billion dollar. I don't think there's an effective way to tax that.
https://knowyourmeme.com/memes/jojo-whispering-to-surprised-emma-roberts
movie clip: https://www.youtube.com/watch?v=Qzfis2TQ-Pc