100% security exists technically, but is difficult to attain, but we should try to get as close as possible.
I tend to agree with this, through knowledge and skills, this will be attained.
Technically, I often hear people who have been scammed as their cold wallets, most of them successfully store their coins safely because they know how to minimize the risk of keeping their assets in the virtual world.
But yes, there's no 100% safe in crypto space.
Everything valuable can be hackable even online or offline, the best thing you can do is minimize the risk.