With any public opinion survey there's going to be a certain amount of "noise" results. You can't _force_ people to give serious answers. But if your methodology is sound (Morning Consult's certainly is) then they will tend to cancel each other out.
You can't force people to give serious answers, but you can incentivize them to do so. My guess is that the results would be dramatically better if the respondents were paid for correct answers.
