What's the practical benefit over just sharding a decryption key and handing out multiple shards to each person?
2. The full encrypted text is available to each person, making it vulnerable to a brute force attack at some point in the far future.
I'm not entirely sure if this implementation actually covers that second point though. It could be including the entire encrypted text with each copy. But it would theoretically be possible to protect against brute force attacks in that way.
On the first point, just give each person n-1 shards, each missing a different one. Then any 2 can decrypt. Or configure it for however many participants there are and they minimum number needed to encrypt.