I have to say that I sympathize with Caesar, but my position is slightly different. I think there is a possibility that that objective morality does exist, but we're simply too stupid to realize what it is. Therefore we should try to improve our intelligence, through intelligence amplication, or artificial intelligence, before saying that objective morality is impossible and therefore we should just pursue other goals like survival, comfort or happiness.
Some people have argued that in fact survival is an objective goal, because evolution makes sure that people who don't pursue survival don't exist. But if we assume that everything exists, the above statement has to be modified to an assertion that people who don't pursue survival have low measure. However the choice of measure itself is subjective, so why shouldn't one use a measure in which people who don't pursue survival have high measure (e.g., one which favors universes where those people survive anyway through good luck or benevolent gods)?
