I guess you could make the argument for Rey not showing up. Luke kinda messed up by convincing her to leave Ahch-To, come to think of it. Ben likely would have realized Rey wasn’t on Exegol, and the two of them would have just chilled elsewhere while the Resistance launched an attack on Exegol.
Fairly certain that Finn, Poe, and co. would have gotten rid of all the Star Destroyers in that battle. Their actions never relied on the Palpatine interactions, did they?
Oh boy, I’m never going to be able to forget this plot hole now.
There would never have been a battle since Rey is the one that showed them how to reach Exegol.
That would have left the Final Order fleet free reign to fully deploy and spread out across the galaxy destroying countless worlds and then holding a proverbial blaster to the head of the galaxy.