[plorkyeran]

Approximately no one is paying thousands of dollars to shave grams off an eMTB. There is a small but visible group of people doing that for road bikes and a much smaller group of people doing that for non-electric mountain bikes. There's probably some weirdo out there doing it for an electric mountain bike but they're probably more of a "decorative expensive bike purchaser" than an "actual trail rider".

[troyvit]

That makes sense. If I'm already saying I need a motor to get myself up the trail I'm pretty far from worrying about shaving weight off my bike (or off of myself for that matter).

[glohbalrob]

There are carbon fiber E-bikes, perhaps it’s “few” but there are people paying to have a more light bike since the extra weight up and down hill isn’t as fun

[plorkyeran]

The weight difference between equivalent carbon and aluminum eMTBs is generally around a kg, but the argument for carbon MTBs has mostly shifted away from weight. While carbon fails more catastrophically than aluminum, it's harder to hit the failure point and it's less susceptible to stress fractures. It is also generally argued that carbon is both more dampening and stiffer in the places you want stiff, but it is very hard to tell how real that is.