People tend to think that storing a seed safely and securely is a kind of really hard and technical thing...
It's really similar to using a web based banking system, where you have user ID, password, and nowdays 2FA too
Do they care about them, to store them securely?
Not really, they key in their login credentials at the first phising mail, on a totally unsecure webpage (which looks exactly like their bank's page)...
I know that this is a bit different because in a bank you can go into the first branch and can ask for a new password or new login ID or whatever (after you have identified yourself of course), and this is not possible with bitcoin seeds, but somehow similar...
As long as people don't learn to care about their digital financial data, it doesn't matter if it's fiat or bitcoin, they will take huge risk...
So if they will start to care about storing their everyday login data in a safe place, they will do the same with their seed too, but until then, it will be a big headache, how to do it...