I think the modern Democrat party becoming the Progressive party is what finally did it for many classical Liberals, whose values of personal liberties remained the same, but the Democrat party devolved into something that doesn't represent a lot of voters. The Republican party voters experienced a huge surge since 2016 and continues to grow.
Yes, this is their actual reasoning for their strategy. Where did you find this assessment? Hopefully, some disenchanted Democrats will realize the motivation behind the DEI agenda