On a night dedicated to talking about the safety of US citizens and stopping the invasion on the Southern border, it was appropriate that Haley, DeSantis, and other Trump rivals rallied around the nominee and against Biden. America is doomed if Biden and his leftist allies remain in power, so it's imperative for Republicans to stick together while attempting to defeat the current president.
Haley and Trump's other rivals had no choice but to capitulate to the nominee because he and his authoritarian ambitions run the party and don't tolerate dissent. Everything Haley said about Trump during the primary season — including calling him "unhinged" and cognitively "declining" — remains true, but anyone with hopes of a future in the GOP knows they can't cross Trump.