The Jaylen Brown trade is a watershed moment for leaguewide valuation of advanced stats over traditional ones. A player in his prime with his level of box score stats and traditional resume having such low value is unprecedented.
According to all reports not a single team wanted to give high value for a player who just averaged 29 PPG on a #2 seed and was 6th in MVP voting
The main reason why seems to be specifically his lackluster impact metrics I think this represents a huge paradigm shift that not a single team wanted to bite