Grizzlies
You guys are most likely saying "Ja and Ben don't fit together" but the grizzlies don't care. They traded for Steven Adams, who fits even worse with Ja. It's a good thing that they are trading him away in this package.
76ers
76ers are getting A LOT for Ben. They are getting Jaren Jackson Jr AND Kyle Anderson... No other team will offer that.
Mavericks
The Mavericks are getting Steven Adams, who will fits well with Lukas play style. They also get Dillon Brooks who is an amazing defensive player