Balance, dexterity and coordination can of course be developed through practicing many different sports.
A great tennis player for example, will be applying the coordination principles to a high degree.
The difference with Aikido is in the mindful application of these principles in communication and relationships as well as in sports, in avoiding serious injury in accidents and situations warranting real self defence.
Less fit non-sport driven students will benefit just as well.
Heavy or awkwardly large items need moving with high levels of coordination to avoid injury.