One can easy argue that should be drawn the other direction showing it's the left which has moved further out. The point, which seems to escape you, is both party candidates at this point are terrible choices, the entire system is broken and corrupt, and we are desperately in need of a viable third party. Problem is, the also corrupt media and corporate establishment, which own the whole fucked up system, will now allow this to happen.
Joe Biden was not a terrible choice. He may not knock your socks off but the job will get done. Maybe not your choice, definitely not FDR or Reagan, but definitely not terrible.
Trump on the hand was a terrible choice from almost every aspect of the job from actual management and vision to leadership to basic humanity. The man had very few qualities that suited being president of the United States. Truly a terrible choice.