NSO is bundled with various balance changes / nerfs, detailed in the tips and tricks menu. Chest size was reduced to help discourage stockpiling of resources because imo you shouldn’t be stockpiling outside of train stops and malls. Personally I’ve always limited my chests to a row or two, so for me the smaller size is actually convenient.
But I’m fully aware this is an unpopular opinion, so I do plan on making these sorts of changes configurable in the future. Potentially within a few weeks if I can find the time.