Is it safe to call this another safeguard?

[As-Soon-As]

I am thinking, if he has more than one cold wallet and split that into 1.5million each, he would still have 1.5million left, which is what created this thought of mine, is using more than one cold wallet another safeguard practice?

User error is what people are mostly prone to, it could affect overall portfolio, having more than one cold storage in this case looks like a good option? Or not.

Yes, you should never keep all your eggs in one basket, that's why having multiple wallets is the most important thing because your assets will be more secure. If you have more money, you can use more wallets, but you must store the keys of the wallets safely. You should never keep these keys randomly, otherwise the security of your wallet will be lost, so as much as possible, you can write down your password in any way on a piece of paper in your diary and store it safely.
Remember, the more secure your keys are, the more secure your wallet will be, so the chances of your assets being lost will be very low.

[retreat]

User error is what people are mostly prone to, it could affect overall portfolio, having more than one cold storage in this case looks like a good option? Or not.

If I were someone who owned that much crypto, I'd prefer to store it in a single cold storage wallet rather than in multiple ones. That's because it's easier for me to manage a single cold storage than multiple ones—plus, it's not necessary to have more than one cold storage to split assets, since I can split those assets across multiple addresses using a single seed phrase and then manage them without having to store and secure several different seed phrases, which can be more of a hassle than it needs to be. What you need to do is avoid mistakes, rather than adding to your own hassle by having more than one cold storage.

[Creeper0]

When I hear such incidents, one sentence comes to mind, "Don't put all your eggs in one basket". Although such incidents happen very rarely in cold wallets. Still, it is better for us to take necessary steps to stay safe.

Incidentally, I think it was the user's mistake. If a device is not used regularly and is not connected to the internet, then it is very difficult to lose money from that device. The only way for this is user error, if a user accidentally shares his seed phrase with someone or is involved in activities that are risky for the wallet, then such an incident is possible.