If banks actually use blockchain and issue standard central bank currencies or CBDCs which they call, this would be the same as Bitcoin or crypto in general?
No, it won't be.
It is not blockchain per se that is the central player here. If it is, then Bitcoin, alternate cryptocurrencies like the shitcoins and the meme coins that are proliferating nowadays, NFTs, and CBDCs are all equal. But it is not. Bitcoin's blockchain is different to that of Dogecoin's blockchain or a CBDCs blockchain or a certain bank's blockchain or a private company's blockchain. It's the set of rules that matters. It's decentralization that matters.