Veni, vidi, dissentiom
Battlefield 1 right now, for me, is the best game that I have ever played. Granted, I have never played BO2, however all of the call of Duty games I have played lacked sufficient incentive to use strategic gameplay, it just didn't feel rewarding enough due to the fast paced gameplay. Skill and muscle memory, in my mind, seemed to far outpace the worth of critical thinking and strategic gameplay. While COD games are usually fun. I found battlefield to offer more strategic gameplay and a more realistic experience with a slightly slower pace that balances skill and decision making.
granted you could say I wasn't really great at call of duty, which is true(not terrible though). However There just isn't much realism even in the old call of dutys that is present in battlefield, there are more players(more soldiers and more realistic to what an actual battle would look like), vehicles which assist the infantry like they do in any war, bullet drop and drag, and the maps can undergo change, (campers aren't as powerful if you blow up their building). The maps are also huge so on most maps the enemy can't really block you off from flanks unless they do so at the objective.
Don't get me wrong, call of Duty is a great franchise (overall), and many of their games are good, but battlefield feels more immersive and realistic and requires strategy and tactics equally along with skills in order to be successful, while also promoting teamwork through different class roles. So that is why I prefer battlefield 1 to any call of duty or other games I've played.
although I expect when Player Unknown battlegrounds is released it will become a much more difficult decision in keeping battlefield 1 as one of my favorites.