Ha! We’re old-school modems! When we fall down, we screech and make other odd noises!
While Duff has explained what is probably the precise intent of the imagery, even the non-technical viewer will get the idea of the old “hardware” being slow and unsteady, while the tandem cruises effortlessly by them, with it’s two good-looking models riding it.
And while the unicyclists were of mixed age, I definitely got the impression they were generally of an older generation than the bicyclists; old tech. If it were a commercial about unicycling, it would suck. but it’s instead using unicycles as a metaphor for the idea they are expressing. And I think it works.
In a different commercial, the unicycles could be the ones ridden by the good-looking models (very difficult to cast, BTW), and riding smoothly and effortlessly through intricate twists and turns that the rival tandem can’t negotiate without having to stop and lift up the wheels. Fill in the blank with what technology or idea could be expressed by that. 
That’s one of the cool things about being a unicyclist in the LA area, especially if you can create your own work schedule; you can go to auditions and be in commercials or other TV/movie projects!