In excited about 1k brains and in general biological research to inform AI! But I don't understand why folks doing serious work on the biological/artificial bo

In excited about 1k brains and in general biological research to inform AI! But I don't understand why folks doing serious work on the biological/artificial boundary push claims about which mechanisms are "necessary" to produce intelligent machines. Hasn't our own progress towards understanding biological intelligence been a series of theories that supplant and reinterpret another? Don't we frequently find new biological mechanisms for information storage and computation that run parallel to presumed dominant paradigms in impactful way? Why need a discovery to be necessary rather than useful or inspirational? I don't think it's common for hard science communities to describe results in terms of what is required, as opposed to what's possible.