In short, yes. Cold wallets can absolutely get hacked. However, it is much more difficult to hack a cold wallet than a hot wallet since the former requires physical access to the device storing the private keys. That said, even cold wallets are not entirely immune to hacking and there have been several notable instances of cold wallet hacks in recent years.
One of the most famous examples of a cold wallet hack occurred in 2015 when Bitfinex, a major cryptocurrency exchange, lost 119,756 bitcoins (worth approximately $72 million at the time) due to an alleged security breach. Although Bitfinex claimed that only its "hot" wallets were compromised and that its "cold" wallets were stored offline and therefore safe, many experts believe that the hackers may have actually gained access to the exchange's offline storage devices (i.e., their "cold" wallets).
While it is certainly possible for hackers to target and successfully attack cold wallets, it is generally much more difficult than targeting hot wallets since they require physical access to the device storing the private keys. As such, if you are looking to store your cryptocurrencies in a safe and secure manner, you would be wise to keep them in a cold wallet rather than a hot wallet.