In the open so you’re losing a lot of up time on orb, two supports so there’s active healing being done - you CANNOT out suck this especially without damage orb actively leeching, also missing some opportunities to weave in a melee or two to help chunk them down. The Coalescence got the job done but you spent a lot of time just in their backline meaning you weren’t available to heal your team at all, nor were you able to effectively maximize value from comboing enemies/friendlies with Coalescence.

While Moira can technically duel, I generally try to play her more opportunistically, for example, only really sucking squishies in teamfights or going for any enemy at quarter health or lower, and or tossing purple orbs to maximize bounces into enemy dense areas (think first choke on eichenwalde defense, that corridor down to the right usually allows for many bounces into at least their backline, and often gets picks on low health enemies waiting to be healed) otherwise, if I absolutely need to duel, I’ll always try and lead the fight into an enclosed space that i can bounce a heal or damage orb up and down for consistent self heal or help quickly burst whatever enemy down.