Canon because you get the Atropos sniper rifle on NG+ and fly through the game as a victory lap with an overpowered team.

For the first playthrough, the player goes loud if they're gated by stealth and isn't canon lore, but this post specifically mentions the Atropos. Edit: For a week after release, stealth was actually mandatory.

After playing RC:CB recently... Man. Guns blazing on stealth is plain more fun in this game after you did a few stealth missions the 'intended way'.