This splitting of seed phrase words into multiple parts sounds a lot like Shamir Secret Sharing, but you are not really eliminating single point of failure like you said in your video.
Other dangers of using something like this is that there is no standardized implementation for this method, math can't be verified by different participants.
It's much better to use regular Multisig solution that is proved and tested for years, but I would like to see some documentation for your Social Recovery feature.