Why are US citizens not allowed on Binance?

Could you elaborate on the reasoning behind the prohibition of US citizens on Binance? I'm curious to understand the specific regulatory challenges or compliance issues that have led to this decision. Binance is a leading cryptocurrency exchange, and given its global reach, it seems surprising that US citizens are excluded. Is it due to concerns over the lack of appropriate regulatory oversight in the US, or are there other factors at play? I'd appreciate a concise yet thorough explanation of the reasons behind this policy.