The review was written while the game was still in development.
It's funny that there is a page for this game, although there were not even rumors.
At one time I really liked Metro 2033, not so much but still liked LL, and Exodus was an atmospheric adventure, which I would probably call the best part.
I think it would be right to expect further progress from Metro 4. the developers have proven themselves to be masters of their craft, so in any case, I will be happy with the announcement and, accordingly, I will expect new mechanics, new beautiful locations, atmosphere and adventures with new characters from Metro 4.