The Lee Sedol bit omitted what made it relevant, so to fill in the context; if you go to the WP article for Lee Sedol, this is how the summary now ends:
On 19 November 2019 [ie. 3 years after losing to AlphaGo], Lee announced his retirement from professional play, stating that he could never be the top overall player of Go due to the increasing dominance of AI. Lee referred to them as being “an entity that cannot be defeated”.
The Lee Sedol bit omitted what made it relevant, so to fill in the context; if you go to the WP article for Lee Sedol, this is how the summary now ends: