Ok, so there are no miracles after all and in the end the seed phrase IS your private keys and your wallet.
I am still not convinced that a hardware wallet is always good. After all, it’s a physical evidence that you own crypto, and don’t tell me about devices that fake a different set of private keys.
Now let’s say I am doing following. I don’t need a regular access to my crypto. I want to keep and accumulate them (let’s say Bitcoin only) for a very long time.
I take a PC without a hard drive, create a Linux live CD (hope they still exist), start live CD, boot into the system created on the ram disk. I connect internet, install a crypto wallet program, write down the seed phrase AND the public Bitcoin address. I shut down the PC, all information is gone. Now I am sending Bitcoin to the address that I have written down. I don’t need my private or personal keys to check the balance and transaction history of my address. With the known address I can use Blockchain scanner to see them on chain.
After 10 years of accumulation I have 10 million CHF (3 million inflation corrected) worth of Bitcoin in my account. I take my seed phrase, take any crypto wallet, restore keys from the seed phrase, transfer them in portions to Union Bitcoin of Switzerland or Crypto Suisse, sell and live happily ever after.
Do you see anything wrong with the technical aspects of this plan?