Subjective and arbitrary are not the same in this context. If it was arbitrary then you could randomize the outputs and see no correlation between experts and non-experts on determining what was tasteful and what wasn't. Thats not true of 'taste'. Taste is subjective in that it is highly influenced by society/culture/history but experts agree on what is tasteful and what isn't within those bounds.

Now preference is arbitrary and subjective. If you just like something even if its not tasteful that is fine, even for experts and I don't know that it is problematic in buying a house that isn't tasteful other than it is a signal that experts were skipped in certain design phases of the project.