Christie has no chance of winning. His whole campaign has focused on alienating Trump’s base (the populist base, often called the “deplorables”, who would abstain rather than vote for Christie).
To win, a Republican needs to unite the Republican party and appeal to independents and non-WOKE Democrats. While DeSantis has already alienated the populist wing, both Scott and Haley, both with good Reaganite/Tea Party backgrounds, are avoiding burning bridges to the MAGA wing of the party (though their best chance of winning the nomination is for Trump to drop out and endorse/anoint one of them).