It will be a short review:
I watched this a few monthes ago while I did see a bad rating for the score of the anime I don't see any explanation as to why (only one review tries and has a bad score)
If you want to watch this anime for action skip
If you want to watch it for a realistic story ( on the technology point of view) skip
To be blunt it goes well in depth on a psychological side, the characters if not too complex ( which would make the anime totally uninteresting because nothing would justify it, "normal" people don't have a really deep personality ( not as much as some seems to believe ) but they do have one which can't be seized whole in one smooth movement ) are well written and following them and their reactions is interesting the backstory is bit by bit discovered and marked the people they are "now"
I think that's all the end was pleasant but not amazing