Lots of examples of diversions and technical issues often due to winter weather and how eu261 would cover (rebooking and duty if care obviously not compensation). Myself I was caught on a Vancouver to lhr that was diverted due to technical issue and I was rebooked by BA onto another carrier.

under EU law a flight diversion is treated as the same as a flight cancellation. Lots of examples under case law you can google.

not saying that QF did anything wrong, simply that in your example BA etc would have been obligated to provide more options. To answer the question.

QF did what they needed to. Other airlines will have been obligated to do more.