From what I understand, the big bang took place everywhere all at once. So I'm not sure that question really makes sense in this situation.
It is talking about how big the now observable universe was at the beginning of the big bang. It's not talking about the entire universe. The observable universe is a perfect but finite sphere. So think of a sphere with a 2 meter to 20 kilometer diameter at the beginning inflating to sphere that now has an 880 yottameter (10^24 meters) diameter.
Oh, it wasn't a question, but an article. And by Ethan Spiegel nonetheless :). Thx for that, I love his content.
Yep, he is my favorite astronomy writer.
The evidence seems to indicate that the universe is flat and infinite. Maybe it has a very slight curve and we don't have the technology to see it yet, but the evidence doesn't show that. It shows that it is flat.