Christians celebrate rape, torture, slavery and genocide.

[John V]

Actually, it's because I don't like heavy things....but......the reason I don't like heavy things is that they leave me feeling somewhat nauseated........and of course feeling nauseated is undesirable because it is a factory standard defense mechanism for (among other things) ingesting harmful substances. So one might say that even though chocolate ice-cream isn't actually harmful to me, it triggers a response similar to things that are, and so my reaction and opinions on the matter are understandably negative (especially when it is compared to vanilla, which does not elicit this response from me).

Are these not compelling reasons

Yes, getting sick is compelling.

to hold a subjective opinion?

It's no longer a subjective opinion.