It all depends on the investor. Some, in fact, a lot, uses hardware wallet for cold storage. For them, it is practicable and efficient in the sense that they are as if carrying their coins wherever they may be. It is synonymous to a tangible property which gives a good sense of belief that one is able to see/experience ones possession. On the other hand, some do not use hardware wallet for cold storage which is premised on the belief that it is creating more risks on the safety of ones property. An example of the latter is when the hardware wallet is stolen or broken. Its natural effect is that it will presumably lose all BTC investments.
Well, my debate with HCP shows that even the loss of the hardware wallet does not mean the BTC is lost too because the owner can recover the BTC thru the seeds and passphrases (which needs to be secured too).
However, my point is if BTC can be recovered thru seeds and passphrases, then why not just secure the BTC with very strong encryption directly on the private keys instead, for cold storage?
With a hardware wallet, the owner will have to keep buying a new one if the previous one is lost. HCP argued that's not the case, but of course if the owner wishes to continue using BTC for cold storage plus spending, he has no choice but to spend for a new hardware wallet. And for purpose of spending, hardware wallet is not the only option available. Desktop wallets can serve the purpose too. However for purpose of cold storage only, then a digitized paper wallet (i.e. store it digitally instead of printing it out) that is strongly encrypted is the best and cheapest way possible. For short, a strongly encrypted private key that is generated offline. It's digital, which makes it 100% portable anywhere in the world. You can store it in your email inbox, instead of dependent on bank vault or something like that. Multiple backup can be made cheaply (because it's digital) without the need to buy another wallet. Hardware wallet can do the same too, but without the convenience and control.