I think finding a way to quite literally build a 'brain' that mimics all aspects of the human brain including: Size, shape/areas/etc that is essentially a mechanically cloned brain like a mechanical heart or lung (Similar to the organs in Bicentennial man), may be the only way to get true AGI.

Simply put we need to work more on mirroring nature and biological brains to get computer brains that function like human brains. Even neuroscience still debates on what consciousness even is.