First of all, this is not entirely correct. With a hardware wallet or any software wallet, the user is in control of the seed generation process. They generate a seed.
Of course, an internet-connected device like a software wallet can only be as secure as it can be. However, with a hardware wallet, a user can choose to go with either dice-generated randomness, a multi-sig wallet, or even use a strong passphrase on top of a single-signature wallet to protect their funds completely.
Truth be told, we do not see people who exercise good security hygiene with their seed phrase randomly losing their funds. Those instances do not happen unless someone intentionally puts backdoors into a hardware wallet.
This is why users should use highly sophisticated and reputable sources for their fund's safe storage.