EDIT because I veered away from the anecdote about my wife and I: She looks at what I look at, and especially what I shared above, and she concludes that a lot of doctors are used to listening to guidance from above because they don't have time to read primary literature on every single new cutting edge thing. If CDC says HCQ and Ivermectin don't work, they're not going to question it. Why question it when questioning it can cause you to lose your job?

Explained in more detail in this American Thinker article