The internet has democratized access to courses as people can now know more information than ever before without actually traveling themselves. In the old days (pre internet I guess) we would send for a travel guide from one of the tour companies or trusted source that was a pamphlet or book we could use to plan our trips and get to know courses. Tour operators had much more value then with insights on "hidden gems" and sequencing of an itinerary. Like the travel agent, I'm sure their business isn't as big today.
The down side is almost anyone can post their opinion on a course, so it is up to the reader to decide what is a trusted source or not. I see the positives far outweighing the negatives. Just have to have a quite dense strainer to filer what is out there. This site being one such resource others rely on.