So I don't expect DeSantis to do anything different than celebrate his victory, serve as the Governor of Florida, and wait to see if Trump further self destructs, or is indicted, has a health issue etc.
...Which is exactly why Trump doing what he did was so dumb. It was completely predictable that a lot of Republicans would be ticked off at him publicly mocking two very popular and successful GOP Governors. The Asian component of his comments about Youngkin was particularly stupid.
So the irony is that Trump's own pre-emptive attacks that he apparently thinks will discourage challengers actually have the opposite effect because they weaken his support and make a potential challenge more likely to be successful.
I imagine both DeSantis and Youngkin are just sitting back and hoping that he keeps doing it.
Possibly, but don't underestimate how much damage the attacks from Trump may actually be doing to them, especially DeSantis.
Trump still wields immense political power, rising to an almost god-like figure in some of his supporter's minds. There are many here posting that they used to like DeSantis, but now that Trump has come out against him, they are now fully against him and behind the scenes looking for every piece of dirt they can find.
It's unfortunate, but when Trump presents this "No one else shall come before me" persona, then in the minds of his followers anything that even potentially stands in his way has to be destroyed as a false idol.
So Trump is hugely damaging DeSantis and Youngkin within the ranks of the Trump diehards, some of which would actually be needed to ever win a general election, even if DeSantis or Youngkin don't even run until 2028.
Therefore, my guess is, they'd prefer Trump to knock it off and focus on the Democrats instead.