The context here is using it as a tether around a conductive cable. It only needs to be unwrapped and wrapped around a drum once every time the kites take off, not every few minutes like in ground gen. Dyneema is more abrasion and uv resistant than possible alternatives IIRC.
I imagine abrasion becomes an issue you need to account for again if the tether needs to go at the same speed as the kites, just like abrasion is/was an issue for conventional wind turbine blades: Aluminium rigid wings? + Blade Materials & Erosion I don’t know how much a tensioned dyneema tether with a conductive core going at high speeds absorbs the impacts from or is abraded by sand, rain, and so on. Maybe you’d want to put sheathing around it.