The whole security system for bitcoin is not that it is impossible (which would be good) but that it is vvvveeerrryyy unlikely.
It is impossible to have a security system which is impossible to hack, and as far as security systems go, bitcoin's is pretty darn good.
Given that most 2FA codes are 6 digits long, there is a 1 in 10
6 chance of someone guessing your 2FA code.
Assuming an average house lock as 8 tumblers, and each tumbler can adopt one of 10 positions, then there is a 1 in 10
8 chance that someone will be able to guess your exact house key shape and unlock your door.
Given a standard credit card has a 15 or 16 digit number on it, there is at most a 1 in 10
16 chance that someone will be able to guess your credit card number.
If you use a password manager to generate a long and totally random 16 character password, drawing from the full ASCII 95 character set of upper and lowercase letters, numbers, and symbols, (e.g. CY\u4"=t{rV%;N9S), there is a 1 in 4.4*10
31 chance of someone guessing it.
The chance of someone correctly guessing your password, your 2FA code, your credit card number, and the key to your house simultaneously is 4.4*10
61, which is still around 2 thousand trillion times more likely than them guessing your private key.