Jancovici said a lot of stupid things also, although it seems that he recently acknowledged that renewables could make an impact (and not just "l'épaisseur du trait" as he always said). I'm not sure what you mean by "degrowth, relocalisation, lower consumption are all solutions that would work better than technology". People in general do no want to consume less, or buy more expensive stuff created locally, so I think it's easier to create new technologies than to change people mindset, although we probably should try to do both (which we are).