Hi, different people have different opinions on it.
Actually, in my opinion, "write it down on paper" is idealism. I think it is not the best way. To be honest, for now, fewer and fewer people use paper. I think we need to find a new solution to help people store their seed.
By different people you mean you and then everyone else? Writing your seed phrase down a paper provides basic security, using two papers in two different locations is almost foll-proof.
For the storage problem, I think it's a trade off. There's no absolutely safe space to store the seed(including paper).
There is no absolute safe place but paper and ink has been used to send down information from one generation to another, if done properly, with a piece of paper in a book and not just a single sheet and then duplicated, it can be a safe storage for your back up.
The customized phrase is stored in your brain(that's very important).
Phrases like "store" does not apply to the brain, you try to memorize things but cannot copy a piece of data to your brain for storage.
Think of how many things you forget each day, your keys, wallet, why you stepped into a room, the lyrics of that song you could sing by heart and on. Your brain is an exceptional organ and can retain incredible amounts of information, but it is still a human organ and can be affected by stress, age, injury, overload, nutrition, and other natural activities.
- Jay -