Standardized tests don't have to be multiple-choice tests from a question bank, though. You can have practical sections, like in the CCIE. You can have long-form scenarios you have to analyze like on part 3 of the CFA. You can have the exams only given on specific dates at specific times of the years, as is done on several exams, so that the questions are always secret and not reused.

The highest quality certifications comnbine more than one of the above techniques. For instance, you might make phase 1 be just a multiple choice test. This mainly acts as a filter so that not too many resources are wasted scoring the more comprehensive sections for test takers who aren't really serious. Then phase 2 testers might take a more open-ended test with essays, etc. Finally, people who pass phase 2 might have some kind of practical, similar to medical boards or the network building in the CCIE.

This kind of process might not be cheap, either. A lot of people's time are involved in creating, administering and grading of this kind of rigorous testing process, but it even if it costs $2000 - $3000, it is still much cheaper than a university. It is still much more egalitarian as it is not open only to the chosen few.