As others have mentioned, BMJ is in emotional stasis due to drug use and mom fucking. He has his basic needs catered to and is subconsciously terrified of having to be responsible for himself. He also has no real life experience or context points. He's probably never had more than a few thousand in the bank at most. $60k and $200k are the same number to him and he doesn't really know what either means because he's never had to handle any type of finances on either scale. They're just both really big numbers and he sees an easy path to get even bigger numbers than those and doesn't really comprehend what the amounts he's winning or losing truly mean.
If his dad cut down the internet and forced him to take that $200k and start a life for himself, he'd waste it door dashing every meal, buying clothes and expensive sunglasses and a Range Rover with 100k miles on it, and drugs. He'd be back home within 18 months.