I based my assessment (Cuban's wealth wouldn't decrease but probably stay the same) on the change in his net worth from 2023-2024. Those estimates are probably low and were from the same year he launched his mail-order prescription company, which likely reduced his gains.
As you pointed out, a wealth tax like Warren's likely wouldn't reduce his wealth, just make it grow slower. Which to people in Cuban's tax bracket is just as bad as robbing them and then leaving them to die in a ditch.
Yuuuup
I just can't imagine having that much money and then not wanting to use it to transform the world in some positive way. Any of them could use their business experience to create worker-oriented systems that were self perpetuating, profitable, and turned their founders into cultural gods.
But no, they just want number go up