I think that depends what kind of introvert you are. I like big open offices because I feel "anonymous" there and it's very easy for me to disconnect from what's going on around me and do my own thing for hours, and then speak with anybody from my team when I need to. If there's some person around with whom you don't connect very well no bad atmosphere is going to occur unless you force it. I don't need a big bubble for myself, I can create a small one easily.

For me a small office with 2 or 3 people is more stressful, it makes me more aware about what's going on around me because it's a more personal space. If you don't connect with somebody in there, the bad atmosphere is going to fill the small office very fast. My bubble is going to trip onto somebody else's bubble more often than in a big space full of people because there's less neutral space around.

Not sure if that makes sense at all... but it does to me.

It really comes down to this. One of my psychology textbooks characterized the basic distinction between extrovert and introvert as the following:

Extroverts become uncomfortable with a lack of external stimuli and thus prefer to surround themselves with stimuli.

Introverts become uncomfortable with too much external stimulus and thus prefer to isolate themselves from excessive stimulus.

To me that basically directly quantifies why some people thrive in an open office and other suffer. I'm not sure what the solution is to requiring essentially two different environments depending on a person's makeup.