It's like there are three topics and you mix them all, different wallet have different advantage and disadvantage, different risk and different way to make it secure.
From your thread, any kind of wallet is not safe, this will make people confused which one they should pick. Cold storage is safe because it's offline, which is correct, but you mentioned if hardware wallet might be vulnerable too, which is also correct. But any problem has a solution, you didn't show the hardware who're not vulnerable.
Example this one
ESP32 chip who used by Blockstream's Jade, the other hardware wallets e.g. Ledger, Trezor or Coldcard are safe.
Innovative security solutions such as biometric authentication
Not really, there could be false positive or false negative to happen.
There is no advantages that a custodial wallet should ever you that should make you choose them over Non-custodial wallet, promise of higher percentage returns if you stake your assets on them? It's marketing but don't let it get to you.
Custodial wallets are not safe, it's like locking your bank account and dropping the key to your friend or neighbour for safety reasons, you sure know what could happen later on right?
No offers or advantages from custodial wallets that should entice anyone, i have lost good amount of digital assets trusting custodial wallets in the past and it will never happen ever again.