Desantis does pretty much nothing to quell the rumors about a potential run in 24.
Consider this for a moment:
Suppose DeSantis has decided to run, but only if Trump doesn't. If he announced it that way, he'd look like a beta in deferring to Trump. The media would hang it around his neck that he was the guy "afraid" to challenge Trump.
So why do it? If Trump announces he's in, DeSantis can then say "I always intended to finish out my term, and I'm not running. But if Trump says he's not running, the deSantis avoids all the criticism that he was too chicken to run against Trump because he'll never have said he wouldn't run against Trump.
Plus, by not a answering that question now, people who want him to run and are sending him money right now will keep doing so. By the time he does run for 2028, he'll have a very large war chest before even declaring.
In other words, it doesn't make any sense for DeSantis to make any announcement at all,.one way or the other, until after Trump makes his.