It is important to backup your seed phrase but some people said the backup is not good online but which is true because we have seen how hackers was able to see some people seed phrase online and steal their coins. But I have been thinking recently that how can people in countries with natural disaster be able to backup their seed phrase offline? An example is the flooding that occured in Pakistan like 2 or 3 years ago that submerged 1/3 of the country under water. Even if you backup your seed phrase offline in many locations, it is possible that kind of flood can lead to permanent loss of your offline seed phrase.
I'm in a country where every year we have natural disasters the worst are typhoons and floods, our country recorded one of the worst typhoons in modern history and I have a friend who experienced this and when I asked him if he had saved his seed phrase he told me yes because he has a photographic memory and he had memorized his 12 words seed phrase before that worst flood hit their region.
But not everyone has a photographic memory so they have to think of ways to store their seed phrase, I have mine stored in hardware and that hardware is stored in a safe, I wish I also had that photographic memory so I can keep store my seed phrase, but it's still better to have it stored in a place you think will be safe in case of national disasters.