I think if we do not make a fatal mistake. then all will be fine. and do not fill in the parts of the request to provide a private key.
Even if you did a small mistake, scammers and hackers can still steal your BTCs that is the reason why we really need to be careful. We all know that our private key is one of the most important files that we need to keep as a digital currency investor or user, with that in public, you will be losing your balances. It can be stolen but if we are knowledgeable of securing our Bitcoins, it will not be a problem.
Absolutely! Scammers are very incremental, and have upgraded their tactics to fool and trap people. Bitcoin is prone for stealing like a theft obtaining the password of the account at a storage service. It could possibly happen if thieves break email accounts and asking Coinbase to reset password, and the confirmation will be sent to hackers compromised email allowing the access of bitcoin funds. Bitcoin is secured but it's us who can make security and safety as topmost priority by taking relevant actions to fight against theft or hackers.