There are power calculations being made quietly at every level of society, and the consensus seems to be that while the GOP is taking an "unfortunate" fascist turn, opposing them would threaten continued white supremacy and the interests of the white ruling class.
To oppose the GOP would be to explicitly oppose what they stand for: white supremacy, patriarchy, and the domination of wealthy white elites and white conservative Christianity, which are seen as the bedrock of (white) American national identity.
That simply won't do to anyone invested in the status quo by virtue of their proximity to power through whiteness, maleness, affluence, etc., and that includes a lot of ostensible liberals, leftists, and other reactionaries whose politics centers people like them.
To oppose the #GOP is to oppose the #revolution, People fear the revolution because they fear #equality. Equality would a be change in #privilege -- a downgrade.