It's not better than writing a seed in plaintext, it's worse, because it creates a false sense of security. We have a horrible problem in crypto ecosystem, because people don't understand the basics of cryptography, the security models, which makes them lose money in the long run - threads about someone getting their coins stolen pop up almost every day. And by advising such bad methods you only contribute to this problem, because instead of learning about proper encryption people will see this childish code and think that it's good enough for protecting their secrets. Maybe it will even inspire them to try to create another similarly bad scheme.