It's not that we are getting dumber. We are just changing our skill set. Remembering where to find a set of information or how to find a set of information is more effective than remebering each item in the set. Search engines have changed us so we don't have to remember trivia and can focus on larger ideas that can't be searched.
Except that without knowing those useless trivia you won't even have the chance to draw connections and associations between them, which is essential for working with these "larger ideas" of yours. No, search engines won't make up for simple lack of knowledge. You have to know what to search for in the first place.
This article opened up asking a single question; "what’s the capital of Australia?” -- in an attempt to make the reader feel dumb. The name of a capital of a country you don’t live in is just the sort of data I would classify as trivia. Knowing that there is something called an atlas, or even more precise that there is a book that organizes this sort of information, or even more recently a website that you can ask this question to and receive back reasonable answer is far more important to know than knowing Canberra is the capital of Australia. Without knowing where to find or how to find the answer you would just have to answer “I don’t know”, but knowing these other concepts would allow you to answer “I don’t know, but I am reasonably sure I can find out”.
It should also pointed out that countries have capitals -- is the "larger idea" -- and the fact that Canberra is the capital of Australia is triva. A good way to look at this; things that have unique names but can be categorized in groups are often trivia and the groups they make are the knowledge. The article actually picked a excellent topic to illustrate this notion. The big ideas are countries, states, provinces, territories. Learning the unique names of these things teaching you nothing new -- other than the name. No new ideas are conveyed by learning a new name. Learning that there are states and provinces, how they work, and what their differences is far more valuable than the names of each of the individual states and provinces. So yes, not knowing the triva can still allow you to work my “larger ideas”.