Sample image of Trailbike erosion.
In one word, NO.
There are substantial differences between the two as a riding platform, both in the way they deliver power and a combination of force vectors that involve contact pressure, rider+bike weight. The trail impact damage potential they DO have comes down to how a bike is ridden. Mountain bikes are still capable of making an ecological impact on trail areas without appropriate trail design, trail armouring or riding styles suitable to the area. You can read more on that at http://flowmountainbike.com/features/please-take-the-time-to-learn/
Of equal importance is thinking about how riding needs to be done in multi-use trail areas where there may also be walkers, horses or other recreational area users (the social impact of riding). That's why we advocate for riding in line with the IMBA Rules of the Trail, and recognise the excellent guidance work of groups like Leave No Trace, who've put out specific trailbike resources which apply equally to riders of all kinds.
The following material is set out on the Stealth USA forums to explain the answers to some of the common questions that get asked about Stealth eBike riding and their trail damage potential.
Does the extra weight mean more damage to the trail? No. Sure the bikes weigh about 30kg more than a heavyish DH bike, but it's not the weight that leaves impression on the ground, it's the pressure (Force/Contact area).
Update: The guys at Flow Mountainbike magazine have been writing a good couple of articles on this exact issue, which we thought we'd include as a courtesy for more reading on the issues associated with shared trail use and the need for respectful, careful riding techniques. Thanks Flow!