Keeping such amount of cryptocurrency in an offline cold wallet will always be my first and only available option, and I do agree that storing crypto on online exchanges and offline cold wallet both have their pros and cons, but if you are well experienced in this space, you will agree with me that the pros of choosing to store your crypto on an offline cold wallet very much outweighs it's cons (if actually there is any con in choosing this option).

Over time in crypto, "Not your keys, not your crypto" have become a very popular slogan, which also have become the number one golden rule in cryptodom, this slogan teaches us that which ever wallet that you choose to keep your crypto on, which you are not in custody of the private keys or seed phrase to that wallet, it simply means that you have just successfully handed someone else your crypto to keep for you, and that person may decided to do anything with it, he or she may sell it, use it to do business, make huge profit through it and not pay you a dime as interest, or worst of it all, he or she may decide to run away with this funds, by simply moving the funds to another wallet that you have absolutely no access to.
So, it's always better to keep your crypto in a wallet where you and you alone have access and control the keys, and the best option in this regard is offline cold wallet.