About 10 years ago I did some test rides on the fat tire 29s. I thought that they were big, clumsy, and slow, particularly in comparison to my hybrid with 700c32 tires. When my knees finally made riding less fun, I put a 500W geared motor conversion kit on the hybrid - moved up to 700c35 to compensate a bit for the added weight. 5000+ miles later the only traction problems I have encountered are in early spring where some shaded trails still have a bit of snow or ice, and I am cautious about cornering on wet leaves in the fall. It still handles fine - pedals and coasts without the assist just like it did before the conversion. That is a good thing because I had to pedal it home once when the controller blew a MOSFET.
I will concede that the fatties have their place but they seem totally ridiculous on a paved bike trail. As for the clowns riding the trails at 30+ under throttle - there will always be fools..........