Is there even a big difference between having everything at high vs having everything at ultra? On this PC I've always had it at Ultra (fully maxed) because Geforce Experience believes it to be "optimal" for my system and I haven't paid much mind to it but then I noticed that shadows are at ultra quality as well.
In my fair opinion, shadows look like [censored] regardless and I've read that people recommend actually dropping it from ultra to say high or medium because shadows are what can kill a relatively good PC FPS wise.