in my opinion bitcoin is safe. it's secure for transaction. your wallet is be protected by number secury that you save. I think bitcoin is unhackable.
but it's still on the internet dude. i've lost my sr member id including the email and the blockchain(in 2016). but now i've recovered that(several month ago), and someone has loan using my acc and drain my blockchain. i don't know these such things can happen, sometimes i just posting while playing dota's in the internet cafe or even gamble too. the lesson i learned is: i haven't open my acc while using none of my internet connection, neither public wifi nor internet cafe