I know that this is duplicated with MC-276345 but MAY I help you tell the reason? 

Description

1. Place a boat, any variant. 

2. Switch to creative mode. **

3. Middle-click the boat, and you'll find that it crashes. 

Reason

"class cqh" (Boat) has a function "cvx cqh.dK()" (Boat.getPickResult).

That returns a new "class cvx" (ItemStack) of function "cvt cqh.al_()" (Boat.getDropItem).

"cvt cqh.al_()" (Boat.getDropItem) returns "cqh$b cqh.w()" (Boat.getVariant)'s "cvt cqh$b.d()" (Boat$Type.getBoat) . 

And it seemed like "cvt cqh$b.d()" returns null, then "cvx.<init>(deu, int, ku)" (ItemStack(ItemLike, int, PatchedDataComponentMap)) crashes.