As someone who doesn't fish professionally, I've no opinion on it's use in the big leagues. A few folks have already noted a salient truth: the pros' job is to advertise.
The point about accessibility in high school leagues (or, say, opens) resonates with me, though. If FFS is beneficial enough that it stratifies the field between users and non-users, that's an issue that will ultimately dampen interest and participation in the sport. Not great.
In lakes around here, I've noticed quite a few more boats spending their time offshore. It takes pressure off the bank where I usually patrol, not only for the fish, but the added experience of seeing more birds, otters, turtles, flowers, trees, etc. More power to the offshore folks if they are catching 'em, but I go fishing to get away from screens.
Regardless of what happens with electronics in competitions, I would love to see the conversation shift to conservation. Do we need to revise bag limits in response to more effective harvest by folks with FFS? Are other factors like pollution or invasive species having more of an impact? Protecting the sport means protecting the ecosystems where it's played.