Yes. If you want your beliefs to pay rent, then you need to choose between features of reality rather than simply choose arbitrarily. Is there anything else that you believe arbitrarily? Why make an exception for moral philosophy? Reminds me of Status Quo Bias or keeping faith even after learning about other religions. Can you name a relevant difference?
It sounds silly and arbitrary when you discharge the references:
“The universe should be made to maximise widrifid’s utility (best satisfy widrifid’s preferences over possible states of the universe)”
Why not replace “widfirid” with “amcknight”? The fact that you happen to be yourself doesn’t sound like a good enough reason.
Is there some reason why moral philosophy can’t be arbitrary?
Yes. If you want your beliefs to pay rent, then you need to choose between features of reality rather than simply choose arbitrarily. Is there anything else that you believe arbitrarily? Why make an exception for moral philosophy? Reminds me of Status Quo Bias or keeping faith even after learning about other religions. Can you name a relevant difference?
That sounds like a good description of moralizing to me!