I mean, Palpatine has to have some sort of first name, right? Maybe it’s just me, but I wouldn’t like it if they kept calling him “Palpatine,” without even identifying his full name.
I always loved the end of BEOWULF where king Hrothgar say, “I am so glad you came, Jeff Beowulf!”
That’s not really the same situation. Beowulf is a legendary mythic hero from a culture that might not even have had multiple names, and Palpatine is a silly character in a movie about space wizards. As long as they don’t mention it in the movies (which they haven’t, so far) I’m fine with him having a first name.