The AI you read, as a English speaker, will not have trawled sources from the 7,000 + languages in use around the world. The "points" it makes are culturally-specific, much as "IQ" tests are culture-specific. It's not expanding knowledge across intellectual or cultural boundaries. It's providing a precis of what is already known within those boundaries.
What AI regurgitates is what a human has programmed it to do. It produces the end result for you, as a user, quicker than a human could assess and write out for you. But speed doesn't neecessarily = good information. You, the user, are still responsible for judging the worth of the information.
Given that yesterday you posted three articles that directly undermined the claims you were making (which, therefore, you clearly hadn't read before posting) this last point has possibly gone way over your head. AI is a tool, with specific, limited uses, not a replacement for human effort. Tools are mechanical. As @Frequency points out, they cannot substitute for human understanding of context, morals, nuance, history - all of which are essential components of decision-making in many areas, including trials.
As for "how good/effective have jury trials been for society?" How old are you, 13? Stop wasting the time of posters who've bothered to respond thoughtfully to you by posting teenage inanities.