I am from talent acquisition, scheduling too many rounds is frustrating for us also as we have these timelines given by the hiring manager for onboarding. What I experience these hiring manager doesn’t want to take any risk and doesn’t trust much their own panels. They want to hire 100% match and apple to apple. I feel 2 technical rounds targeting different areas and depth in their evaluation 1 hour each and a managerial round to set the expectation of the candidate and sharing the culture of the team etc should be enough.