Right, so it stores your private key. And if that's lost, you lose access to your crypto forever, right? Are you saying you have the private key backed up somewhere? If so, then the hardware key doesn't seem so secure after all, wherever other places the key is stored could also compromise your account.
The sole purpose of a hardware wallet is for the user to be able to spend the funds without exposing their private key to unnecessary risk. In a sense, it is designed to secure the private key by keeping it within the device and making it resistant against any malware attacks, or other extraction techniques. You shouldn't bring your hardware wallet everywhere in the first place, it's another unnecessary risk.
Seems to me if your hardware wallet is destroyed, and you forgot to keep your seed phrase safe because the hardware wallet gave you a false sense of security, then it's all over.
Which is why it tells you to keep the seeds safe.
How is a hardware key any better than a software wallet if the only thing protecting it is the seed phrase? If someone got your seed phrase, then they can make another hardware key, right? So, no different than a software wallet, except that the hardware wallet is offline.
Hardware wallets are not offline. The way they are designed makes it immutable to malware attacks as the microcontroller is designed to not get compromised through the USB. Airgapped wallet does the same thing with one key difference with hardware wallets. The seeds are stored within the secure element which cannot be extracted or brute forced in the event that it gets stolen. They are specifically designed to resist physical attacks and sidechannel attacks. It depends on your use case; if you're going to keep your cold storage in a safe and don't mind the hassle with using it, then it'll be better that way.