Apples and roller coasters. Kavanaugh was already in the public eye as a SCOTUS nominee. Not that death threats are in any way acceptable, but when you accept a SCOTUS nomination you also accept the visibility.
The WB never volunteered to be a public figure, and making them* into one – when Trump has already suggested they be executed as a spy – puts their life in jeopardy.
(*No idea of the WB’s gender, and too lazy to rework sentence for proper neutrality.)