You have data to back that up I assume?
Biden had polling in his hands that said Trump would get 400 electoral votes against him on the day he decided to run for a second term. Then he held on just long enough to make certain we would have no primary and be stuck with a candidate who couldn’t shake the stink of his presidency.
Harris lost the popular vote by over 4-million votes. There aren’t that many “leftist extremists” in the whole damn country, and only a small subset of those wouldn’t have voted for Harris.
The vast bulk of those who stayed home were left leaning apolitical normies. Most of the country fits in that group.
Best I could do without a definition for the stupid use of “leftist extremists” with no definition. My point is, there is zero evidence to blame this election on leftists of any stripe.