Could that desire not to lose altitude be linked due to the weather deviation,(which I think could be one of the psychological factors affecting the PF's initial reaction) in that they were just clearing the tops of a cell and were worried about the subsequent impact of losing it. Hence the application of TOGA to attempt to compensate for the pitch up.
You know, you may be so on the money.
All the "haters" on here can't even recognise a simple human decision, a decision made in an attempt to avoid further "difficulties".