Pretty much the title
Sometimes your team was fine but the enemy varus did fantastic too and you feel he deserves some recognition
Sometimes you were having some laughs with the enemy lux in /all
Sometimes your team is just bad and you just want to honor the enemy irelia who just played like a beast, just so you can at least feel someone deserving of the honor gets it too
Or sometimes the game was just so good that you feel everyone deserves a bit of love
I suggest re-adding honoring enemy, as an addition, and not instead of honoring one of your own teammates. This can be like the old honor system was like and maybe eventually it can also start generating some kind of reward, the way honoring team does now too.
Sportsmanship is, after all, not all about how you behave within your team, but also about how you treat your opponent.
Plus, honoring others is just fun (imo).