I see absolutely no reason
I see absolutely no reason why an EV semi is allowed to weight more the it's diesel counterpart. Weight is typically determined by the roads and vehicle construction ie tires and suspension.
You cannot subtract the difference of electric motors and diesel drive train to show that ev's are similar in weight. It's simple, take full weight of e-semi and compare it to a similar model diesel and that's the difference. Anything else is a sales pitch and means nothing. So you're at 8-10k lbs difference. If you load both vehicles to the 80-90% max. capacity they say is "typically" hauled and you are still at 8-10k lbs less on the e-semi. Simple math. Yes I'm ignoring the 2k lb bonus given to e-semi because it's not any safer and they shouldn't be given an "bonus". Take the 1k range of a diesel before refueling compared to 500 on the e-semi and its not going to get the load there any faster and would actually require more trips taking more time which will increase cost of product not counting for the cost to by an e-semi. In the city with smaller loads, yeah an e-semi may be beneficial but not on a long haul with heavy loads.