Later, I found that the consulting institutions that consulted me were not professional. Generally speaking, they didn't hear the questions, answered them in depth, and leaked questions, which violated my professional quality. The answer is very shallow, in fact, you can find it online. It's meaningless to fiddle around for that consulting fee, so I don't want to answer.
Later, I found that an overseas consulting agency asked me for advice, specifically asking what the consultant's employer was. Turns out they don't know. It happened during the Sino-US trade war that they suddenly realized that they would not be used, right? ! From then on, no one answered all the questions, so I hung up.
For a little consulting fee, it is recommended not to answer inquiries of unknown origin.