its weight is around the same as Oculus(Meta) Quest 2
And people have been using Quest 2 for hours, there are even some headstrap+power bank accessories for that too
Quest 2 (503g) lasts 2+ hours
BoboVR B2 battery (140g) last 2+ hours
So people have been using 650g headset for hours normally before
Also, motorcycle helmet weight 1500g
Safety helmet Weight 200-600g
So I think the weight is not the problem, just they aren't used to that