Why is XMR not on Coinbase?

Could you please elaborate on the reasons why XMR, or Monero, is not available on Coinbase? I've noticed that many other cryptocurrencies are listed, but Monero seems to be missing. Is it due to regulatory concerns? Or perhaps Monero's privacy-focused nature poses challenges for Coinbase? Could you provide some insight into this matter? I'm curious to understand the reasons behind this decision.