You're putting a lot of weight on the word basically in your first sentence - the reality is that gig workers have characteristics that clearly fall under the classification of employees and others that clearly fall under the classification of contractors.

The problem with your argument is that because the law is ambiguous with regard to this situation, the labor secretary is effectively making law by choosing a particular interpretation of the law.

Though to be clear, I agree with you 100% that this is because Congress is just perpetually failing America through corruption, selfishness, etc., and that failure puts the labor secretary in an unenviable position of having to enforce laws that don't really work for the situation.