Hi Adrian90
No, as the ticket via Bern is more expensive, the fare difference is +CHF 18.00, full fare.
You are welcome to alter your ticket at the SBB travel centre at Zurich Airport to buy there a so called “change of route”.
However, the route via Luzern-Brünig-Interlaken Ost is extremely scenic and well worth to be explored, should you be interested in panoramic views.