Didn't Star Trek teach us better than to hate?
Picard and the Borg.
Picard out and out hates the Borg. He knew from his own experiences that once assimilated a drone could be rescued and "de-assimilated," inspite of that he still killed the Enterprise crewman on the floor being assimilated. Picard in his own mind did him a favor.
Leave no man behind (unless they're being assimilated).
When was there time to rescue and deassimilate that crewmember, or any other for that matter? I must have missed that part.