I'm a long-term customer of Coinbase. Had an account and a card with them for years with no issues. Today I received this:
Unfortunately we have to close your Coinbase account. Before your account can be closed, youll need to withdraw your crypto funds to an external wallet and your cash funds to a bank account associated with your Coinbase account. If you are currently enrolled in USD Coin rewards, you may want to wait up to 40 days before withdrawing funds to ensure you have received all eligible reward payouts. You will not be able to access these funds after account closure. Please take precautions when transferring cryptocurrency to an external wallet as transfers outside of Coinbase are irreversible. Please also be sure to delete any external references to cryptocurrency addresses generated by Coinbase, as funds sent to those addresses will not be accessible once the account is closed. If you have any questions you may visit https://support.coinbase.com.
I heard cases of people ending up with frozen coins and closed accounts without any clear explanation, so you are certainly not the only one.
Some exchanges consider gambling, coin mixing and connection with sanctioned countries as high risk, but they don't need to give you any explanations for closing account, it's in their terms.
I would suggest switching to p2p trading and decentralized exchanges like Bisq, to experience real freedom without kyc.
Unfortunately we have to close your Coinbase account. Before your account can be closed, youll need to withdraw your crypto funds to an external wallet and your cash funds to a bank account associated with your Coinbase account. If you are currently enrolled in USD Coin rewards, you may want to wait up to 40 days before withdrawing funds to ensure you have received all eligible reward payouts. You will not be able to access these funds after account closure. Please take precautions when transferring cryptocurrency to an external wallet as transfers outside of Coinbase are irreversible. Please also be sure to delete any external references to cryptocurrency addresses generated by Coinbase, as funds sent to those addresses will not be accessible once the account is closed. If you have any questions you may visit https://support.coinbase.com.
No reason why, nothing. Is it common? Anyone here also dumped by Coinbase just like that? 
Ne happy they are giving you the option to withdraw coins to your own wallet or bank account. I heard cases of people ending up with frozen coins and closed accounts without any clear explanation, so you are certainly not the only one.
Some exchanges consider gambling, coin mixing and connection with sanctioned countries as high risk, but they don't need to give you any explanations for closing account, it's in their terms.
I would suggest switching to p2p trading and decentralized exchanges like Bisq, to experience real freedom without kyc.