Let's keep this short...
For a show that is ostensibly about realism, it is ridiculously idealistic.
If idealistic fantasizing is your thing, this show might speak to you. But it doesn't speak to me. To paraphrase a line near the end, "this show and I are like oil and water." Initially, I was fairly optimistic. The main character does appear to act like a realist insofar as he tries to accept situations are they are and deal with them accordingly. However, this realism is quickly undercut by the idealistic way in which events occur and play out. There is no exploration of grey areas and morality. The viewer is presented shallow, black and white interpretations of problems that are resolved with unrealistic ease that often came across to me as almost hyper-nationalistic. In addition to this and as is usually the case with harem anime, the show exists as a male power fantasy. Regardless of one's opinion of harem as a genre, however, it is undeniable that the harem genre is inherently unrealistic. The whole point of harem is that it is an idealistic, sexual fantasy.
I rate this show a 2 because it is still better than a lot of the other isekai cookie cutters and as a result I was actually able to finish it. But it's a far cry from what I was hoping it would be.