In response to the arguments put forward by @Adonalsium
TL;DNR - EBikes are the best thing for MTBing since, well, MTBing....
For discussion lets define an E-Bike as an electric assisted pedal bike with a motor around 250-500Watt.
E-bikes do not cause accelerated trail wear due to increased weight.
Ebikes weight about 10kg more than a normal MTB. The total of teh bike, 85kg average rider with water and tools normally carried will be less than 10% difference. Tire choice (size/pressure/tread) will have more effect than the weight difference. Would it unreasonable to argue if EBikes are banned because of weight, so should riders over 100kg.
E-bikes do not cause accelerated trail wear due to increased torque.
A strong rider can output 1000W for a short time, twice the output of an Ebike. Where trail damage occurs for high torque, its when short busts are needed and riders will regularly exceed the torque provided by an EBike. Ebikes are able to produce a smooth power delivery, preventing the 'stall' then burst as a pedal only cyclist climbs a steep section. Overall the smooth power of an Ebike can be used to reduce trail damage and the damage done comes down to rider choices.
That said, some trails may not be suited to EBikes at all, and others may need work on sections to make the withstand the extra power. However most trails that are suitable for moderate to heavy MTB use will easily handle EBikes.
Get over it, there is always someone faster than you, if not, there will be soon. Cheaters will always cheat - ask Lance Armstrong.
They allow users to move uphill faster than unassisted bikes and can create a speed hazard.
The speed hazard is possible regardless of the motor. Its the rider who has control of the speed, not the bike. In the 1990's, walkers used this one as a justification for banning MTB's from trails - yet today mixed use trails are very common. Its really down to the riders choice of speed for the conditions.
Potential loss of trail access if land managers decide to ban all bikes due to e-bikes being classified as bicycles - Again, rolled out by the walkers in the 1990's. Some land and trails may not be suitable for E-Bikes, and some riders will take E-Bike on those trails. As we have today - some MTB'er ride walking only trails. The answer is not to ban them, but to discourage though peer pressure and if needed reporting and prosecution of those people breaking the rules, working closely with land owners/managers.
It allows less fit people to enter the sport and participate on tougher (as in, harsher uphill sections) courses. This is great - the more people participating and getting out, the better for all cyclists. As far as fitness, its flawed to presume EBike riders are 'less fit'. Anecdotal evidence is showing many buy ebikes so they can ride longer and further and have more fun. On average, Ebike riders get more fitness than non-ebike riders as they ride more often and longer.
It is too low a barrier to entry and will attract too many people to trails, which leads to increased degradation and congestion. The more people that ride, the more trails there will be. The trails that are build will be more varied. Compare the trails we have today with what was available in the 1990's when few people rode MTB's.
It will lead to riders riding out into back-country areas when they are ill prepared for it. Same argument used by walkers in the 1990's. At the time I was in Land Search and Rescue, and back country MTBers were a major concern for us. Lightly equipped and fast moving - Distance covered by a biker was four times a walker, area to cover for a missing biker was 16 times larger than a walker. Yet in the 10 years I worked in LandSar, we searched for (and rescued) 1 lost MTBer.
In addition to those there are a couple of other benefits of E-Bikes.
- Older people will be able to remain active longer. This has many documented benefits in terms of health and wellbeing.
- Those who suffer form illness and injury that currently prevent them enjoying MTBing will be able to participate.
- Groups of people of dissimilar fitness and skill levels will be able to ride together as a group, with each person being able to enjoy the level of challenge they choose. The keen three day a week rider getting bored taking her novice boyfriend on a slow and boring ride for her while he's swearing to never ride again. Family groups where Mum and Dad can keep up with the teenage sons and daughters and still laugh and talk.