However, a price-reduction war would be good for the consumers in the short-run. In the long-run, it may hurt consumers as it could result in a monopoly of sorts if one company peters out on the GPU side. I think there is enough work being done by AMD on the mobile side, as well as by Apple and Samsung etc, to power solid graphics on mobile phones, that there will always be competition in the mobile and 1080p realm, and probably even the 1440p realm.
Simply put, as long as AMD can provide better low to mid-range cards (where most of the sales are) than NV at a similar or lower price, they'll probably be in a good place.
In my opinion, however, to drive those sales, they should push out a true 2080 ti competitor, if only for a silly urination contest, because it will show consumers competitiveness, which is, surprisingly, probably of high value among people who buy dedicated GPUs. If they can do it, and especially if they can do it with Navi at a decent performance/watt rating, the price won't really matter as much - the sheer existence of the card will.