"fear of stories like this".

As a matter of fact, Fred Wilson on his blog the day after the deal was announced was asked this by a commenter:

"I was looking for a lively discussion of the FB/Instagram deal today"

To which Fred replied:

"i'm not interested in that discussion really. somehow that takes energy from me. i am not inspired."

As you said "obvious missed opportunities are going to sting"

http://www.avc.com/a_vc/2012/04/life-liberty-and-blazing-bro...