> Also its very hard for someone to crack your bitcoin and find out what transaction you did.

Only the first part of this sentence is correct, the cryptography in bitcoin is designed to give you absolute ownership of the bitcoin you control by means of (Currently) unbreakable encryption. But the transactions themselves are totally public on the blockchain that anyone can look up anytime. Once they know you are the author of a transaction they can scan that wallet for other movements and figure out a lot of info about you. Monero is a cryptocurrency that actually encrypts the transactions as well as the wallets so this does not happen, but it and other privacy conscious cryptocurrencies are not as popular as the ones that reveal your movements by default such as ethereum and bitcoin.

Iirc this was sort of a strategic decision by Satoshi Nakamoto, who was balancing the threat bitcoin could pose to the traditional economy - greater obfuscation would've been possible to implement but he chose not to go that way. As is bitcoin is extremely transparent to authorities and so it's potential for disruption is lower than if it was really untraceable internet money.