The reason that it's unlikely is because there's such a low amount of competitive ZSS players that even do doubles. The only one on the top of my head is Nick Riddle, which he usually teams with a Lucas IIRC.
There aren't many characters that can perform gimmicks or work in contrast with Falcon. The most that they can do is carry the team and babysit Falcon so he doesn't get KO'd or combo'd by stupid stuff, then Falcon can KO, assuming that his kill moves aren't stale. If he's sitting behind and racking up small bits of damage without staling the moves that ZSS can 'GUARANTEE' to hit, then it shouldn't be a problem.
Though I will agree with you, it's unlikely because people rarely use Falcon in the first place. ZSS/Falcon is a pretty abstract team, but it's definantly one of his best.