Real neurons have many other trainable parameters and a lot more computational structure, so this is of course a simplifying assumption, but it is not entirely

Real neurons have many other trainable parameters and a lot more computational structure, so this is of course a simplifying assumption, but it is not entirely baseless either as it is known ANNs can approximate any function in theory, which may suggest synaptic weights do the heavy lifting in biological brains (since what more than general do you need?). Though biological brains are likely overly complicated due to evolutionary baggage. There are hydrocephalus cases which have much reduced brain matter, but still high IQ.[1] The recurrent laryngeal nerves in giraffes is about 4.6 metres (15 ft) because it goes up and down their neck as it could not be rewired more directly during evolution.[2] Our pristine mathematical models and low-noise computational environments are likely superior to evolved wetware hacks. [1] https://www.newscientist.com/article/dn12301-man-with-tiny-brain-shocks-doctors/ https://www.newscientist.com/article/dn12301-man-with-tiny-b... [2] https://upload.wikimedia.org/wikipedia/commons/thumb/7/7e/GiraffaRecurrEn.svg/1280px-GiraffaRecurrEn.svg.png https://upload.wikimedia.org/wikipedia/commons/thumb/7/7e/Gi...