Inherently subjective, but you can still approximate ‘more or less tasteful’ by how many people respond well to it.
Since many of our likes are driven by our shared culture and physiology, many other people will appreciate such creation (even if they don't understand why exactly they like it). Others will appreciate depth of nuance and uniqueness of your creation.
Opposite to taste is approximated "good" average which is likeable but just never hits all the right notes, and at the same time already suffering from sameness fatigue.