The most significant development in the last several years has been the widespread revelation inside right wing circles that leftism and it's ideological underpinnings are secular replacements for religion but are still imbued with strong religious fervor and devotion.
20 years ago conservatives viewed left wing politics as simply the opposite side of the coin operated by the same type of rational people on the right; "they could be reasonable and persuaded" was still the default approach.
Today, we have correctly identified leftism as not a political stance or set of policy options, but as a religion with articles of faith, priests, heretics, and original sin.
Leftist political devotion, as
@The Ugly One so succinctly put it, is faith based and cannot be "destroyed by facts and logic". Whites are evil, browns are good, guns are evil, criminals are good, having children is evil, deindustrialization is good.