No, a conspiracy is when people get together and conspire, i.e. they develop a secret plan of action for nefarious purposes. In the strictest sense, the term “conspiracy theory” just means that you’re theorizing that some people have secretly planned to do something. If you theorize that some wrongdoers have developed or enacted a secret plan, and it later turns out your suspicion was correct, then by definition you had a true conspiracy theory.
Insulting someone via stereotype doesn’t show that they’re wrong. You’ve added less to the discussion than the person you’re attempting to mock.