This hand-wave over designer's inability to build enough slack to deal with Adobe's failure into every project is a combination of unsubtle trolling and egregious sociopathy.
Well, to play devil's advocate, 'planning for the unexpected' should also cover 'a client calls at the last minute with a rush job', shouldn't it? In that case, how is an Adobe outage the consultant's fault?
Yes, a professional should be prepared for unexpected customer requests with tight deadlines. And the response to such a request is to just get the work done. That, of course, involves being prepared for any service outages that might interfere with such work.