When Tim Keller preached his sermons on Luke 15 and wrote his book on the parable of the prodigal son, he treated the elder brother as a type of conservative/fundamentalist and the younger brother as a typical irreligious liberal. This model explains why he is hard on those to his political and cultural right and very accommodating of and compassionate towards those on his left.
But the script has been flipped. Today, in “negative world,” the most smug, censorious, self-righteous, arrogant, condescending, legalists are on the left. Today, it is liberals who bind burdens on the backs of ordinary people, whether it’s provoking guilt for causing climate change, accusations of bigotry for failing to use the right pronouns, or ostracism for holding to the same definition of marriage as first term Obama. Today’s progressive is just a modern day Pharisee.
ADDENDUM: I've been making this point for quite some time, e.g., this talk "Galatians and the Culture Wars" which argues that the real legalists today are found in the world, not the church. To reverse Dostoevsky, "without God, nothing is permitted."