"So much for the tolerant left" and similar conservative snark is a psyop. They imagine it requires tolerance to be a progressive or leftist. We only tolerate diversity, justice & change, in their minds. But it makes their argument for them when it's used by others.
It sneaks in the idea that 'you're still a bigot, you just tolerate this nonsense' or 'you're just pretending to care, we see you'; it's cultural conditioning disguised as mockery.