There are a lot of reviews that pan the series, but the only criticism I agree with is the slowness. I am 100% sure the people there talked faster, walked faster and did not have those long pauses for dramatic effect. That makes it seem unrealistic.
But I think some of the other criticisms, such as comparing it to the Cherynoble series are way off. It is a history for those of us who were in Japan at that time, including me, not a typical drama, and it fills in all the gaps about what happened. That is so good.
I also suspect a lot of the critics watched it in English audio, not Japanese, which makes it seem like a Mickey Mouse cartoon. If you know Japanese, the interactions are much richer in that language, but even if you don't, use the subtitles. The language and demeanor match up better and communicate more. In Japan, it is the empty spaces that count, the unsaid.