This is not a discussion on whether or not true Islamic banking exists or not. As with many things in religion you are obligated to do the best you can under the circumstances. Clients like the topicstarter can't be expected to change the core workings of banking themselves but they signed up with bunq because it was the one bank that didn't pay interest at all nor invested, a best effort in the western society.
It's easy for people to underestimate the stance of Muslims against interest and I'm sure even many Muslims themselves forego on the fact that it's not allowed within the religion but that's also not the point or discussion here.
It's about the fact that there are Muslim clients that don't want to receive interest and are being forced to receive it now, it wasn't their choice and bunq should respect that.
Personally I think massinterest is a great value addition to bunq but please let the users who do not want this opt-out and possibly also opt-out of government bonds.
Do not underestimate the importance of the ban on interest for Muslims.
I vote for bunq to implement a fix for this asap.