As you said, friction would introduce more wear and maintenance. This gentleman's idea is to attach a windmill to drive the rotary induction wheel, which would essentially be "free" heat energy, and an interesting hobby contraption. Entertainment and a sense of accomplishment is probably his main goal.
Its not a brand new idea, just a different application of the principle. Induction generators already exist, and they can indeed be used with windmills, but to generate AC current versus heat energy.
More power to this fun and crazy inventor. Maybe he can find practical and reproducible use for this effect. If not, he's gonna have the most unique water heater ever invented. With this he could make a fully mechanical hot water heater that burns no fuel and uses no electricity. He would just have to make a mechanism to disengage a clutch at the top temperature.