The moment you disabled 2FA, you removed an important level of security for your account.
If your funds have been moved and it wasn't you, most likely someone entered your account and robbed you.
First, I advise you to use a real Bitcoin wallet, not blockchain.com/info.
Second, you should check this page and enable a couple of advanced security options.
Yes, it's the whole block. The hex text is 2.5 MB. Hex has 50% efficiency, so the block is 1.25 MB.
Since SegWit, blocks can be larger than 1 MB. There's a 4 MB hard limit which is almost impossible to reach. (With the largest block to date being 2.4 MB, 4.8 MB in hex)