Dog fighting is not a serious concern in modern fighter combat because missiles have gotten so effective that the current strategy has been forced into beyond visual range combat. And stealth doesn't just "fail". In bvr the first side that sees the other is the side that gets to fire a salvo first, which is the primary advantage of stealth technology: so that the enemy doesn't see you from as far as you can see them. All stealth does is linearly lower the radar return of your plane for a given distance and angle, but radar return is inversely proportional to the fourth power of distance. This means that if you get close enough then any decent radar can eventually make out an f35. The whole point of stealth is to make that distance as small as possible.