I agree with the observation that the left seems demoralized and confused, but I don't think this will lead them to a change of heart. The left is fundamentally a millenniarian cult. When reality violates a cult's predictions, adherents don't tend to leave. Instead, they confabulate explanations for why the predictions were akchually confirmed, and then move more deeply into their delusional belief system.
In this case their cope will be that multiculturalism would have worked just fine, if only it hadn't been for the ineradicable racism written into white DNA. The hostile reaction of whites to second class citizen status confirms that whites are irredeemably racist in essence. Their anti-white hatred will therefore only intensify.
Since the left has achieved total institutional capture, there are a very large number of influential people whose careers are entirely dependent on their ideological faith. Just take one look at the chief constables in any British police department: every one of those soft males and hard lesbians owes their position to DEI, either as supporter or beneficiary. The same is true for most of the police under their supervision. The same dynamic is replicated across the rest of the civil service, academia, the media, and much of the corporate sector.
So what we'll see is a hardening of the elites and their minions. But at the same time for everyone outside the cult, the insanity of the cult's behavior is now obvious. That will make it much more difficult for the cult to recruit, at least amongst the white youth. Those who were merely going along to get along will fall away, taking the appearance of popular support with them. Society will fracture. Elites will react by much more actively using their third world auxiliaries against the recalcitrant native population, censoring the Internet, using the legal system for naked repression, and so on. Society will fracture more, and the violence will spread and escalate.