John Ternus doesn't become CEO until September 1st. If you think that this is still John Ternus' play, Tim Cook is still the one in charge and signed off to start this, meaning "Tim Cook would never have started this" is still 100% wrong.
Tang was never mentioned as a candidate in anything I read over the past few years. He wasn't an SVP.
Sending the notification letters is probably petty though.
But the iPhone is the most valuable consumer hardware product on the planet, and the accusations here is “conspiracy to steal” essentially.
Is it really that petty? Apple should be okay with theft of valuable secrets?