Peace Boaz,
Where there's a will there's a way. There's lots of things that can be done to avoid getting into large crowds. When circumambulating the ka'bah (tawaaf), one can stick to the very outside edge of the tawaaf, where you are not in close proximity to others. You could even go up to the middle floor, where it is even less crowded for tawaf, or even the roof, where it is less crowded still.
When in Minaa and Arafaat you are mainly in tents with others in your group, but when stoning the jamaraat, you can walk on the outside edge of the crowd or even away from them, and change your timings a bit etc.
The rites of Hajj tend to be in large open spaces, so there's always something that can be done to make things easier for yourself.
I don't think there would be any reason for someone to be exempted from the obligation because of this, but Allah knows best.