If you want to understand why Mike Pence is called a traitor, you need to find out who is calling him that. The people who call Mike Pence a traitor are above all radical supporters of Donald Trump. Supporters who worship Donald Trump's personality.
These people value Donald Trump more than the United States. They seem to have forgotten that Donald Trump was there to serve the United States as President of the United States.
Mike Pence has not forgotten that. At one point he had to say stop Donald Trump's repeated attempts to steal the result of the 2020 presidential election. Mike Pence took a long time to react in my opinion. He should have let go of Donald Trump a long time ago. He did so on January 6, 2021, in the best interests of the United States.
American People think Mike Pence is not a traitor, but a patriot. The real traitor is Donald Trump. He is a traitor to the American people and to the United States. He has repeatedly trampled on American democracy when he should have been the guarantor of it.