you say this address belongs to you, right?
did your blockchain.com wallet generate it randomly or did you acquire it from somewhere else (like an exchange, or another similar service) and then import it in your wallet? do you have its private key or just the address?
the behavior looks nothing like a hacked wallet (spend after 1 hour instead of immediately), but it looks more like what services like an exchange or a gambling site,... does.
so does this mean blockchain.com can freely access you account and interfere with the funds inside it and use it as they please? since OP said that he didn't made any transaction to send out the
the transaction he received the only possibility now is that blockchain.com has complete control over their users accounts. if that is so, this is quite troubling.
no. they don't have any access to those wallets i am guessing that the address owned by OP was already compromised and the hacker was waiting to the OP send the bitcoins to that address. if only OP knew that he can use double spend attack to recover the bitcoin.