The safest way to store btc are those cold storage. The hardware wallet would be the best example.
How sure are you that the hardware wallet will still work 20 years later? How sure are you that computers 20 years from now will still use the same connectors? How sure are you that the wallets will still support 20 year old hardware wallets? This does not sound like a reliable solution to me.
In my opinion storing btc in an offline device like computer would be more safe
You think that computer and storage will still be running 20 years later? You are willing to risk what might be millions of dollars on that possibility?
You should not afraid to trust this process and should not be anxious
You should ABSOLUTELY be afraid to trust and be anxious when your bitcoin might be worth millions of dollars in 20 or 30 years, and you need a storage that will last that long.
The possibilities of having the access to your computer are only your family member or people living in the same roof
And any criminals that break in, or any visitors that come to your house, or any workers (plumbers, electricians, delivery, installation, etc). Also any government officials (police?) that decide to investigate your home.
and they can be more trusted more than anyone else.
It's cute that you are so naive. Not everybody has trustworthy friends or relatives. Some people are stuck living with criminals or addicts.
The computer system also can have added security features like securing it with password on specific drive where your btc keys are being stored.
And if you forget the password after a few years?
all keys can be disclose just by the seed phrase alone.
What if the "standard" method of seed phrase generation changes? Then how do you use your seed phrase? You would need to find OLD software from 20 years before that can still run on the modern computer.
This is all that matter and do not get too much worries on everything that might hinder you
There are many stories of many people that lost access to millions of dollars of Bitcoin because they "did not get too much worries on everything that might hinder them".
Cold storage is more recommended to be honest just don't lose the needed credentials to access the wallet because you will be waiting for nothing.
Credentials are not enough. You need to know how to use those credentials.
Storing it in a computer is advisable but given the lifespan of many computers, I don't think that it will be best for the long term because there might come a time when the computer gets broken either by accident or wear and tear,
So it is advisable? Or it is not advisable? You say both. This is very confusing.
I highly discourage storing in computers, especially if the computer is not a brand new one and you are always clicking suspicious links.
Ah, ok. Not advisable. Thank you for pointing out what not to do. This is not every helpful in answering the question of what to do.
Have you considered storing your Bitcoin on an interest account? You earn daily/ weekly/ monthly interests rather than letting it sit idle.
Well now, that certainly sounds like a scam.
And if you are concerned about fraud, those service providers are insured.
Well, I'm glad you cleared that up. Then again, that is what a scammers would say, isn't it?
You can buy a hardware wallet such as Ledger Nano or Trezor and start moves your bitcoin to that wallet.
And in 20 or more years, when that wallet company has gone out of business, if that hardware wallet doesn't work, what do you do then? This does not sound like a reliable long-term solution.