If by this you mean literal outflow of domains, then I agree. But if you mean public relations impact their support of and then half ass retraction of support for SOPA then I disagree. I think the long term effects of all this calamity are something they very much care about.
The person who owns 20+ domains is the type of person who probably is someone who cares about SOPA.
I don't think these numbers, really mean anything, to be honest. But I do think that pissing off the people who are the cheapest customers to acquire and support and the people who people are going to ask where to register their domains at is probably not the best business strategy long term.