Not a physicist, but I was led to understand there is no universal frame of reference. You can't base time on deep space as if time was the same across all dee

Not a physicist, but I was led to understand there is no universal frame of reference. You can't base time on deep space as if time was the same across all deep space, because it isn't. Right? A local time "correction" is easy when you compare against exactly one other point in space but if you want something like an universe-wide UTC that everyone can correct against, it can't be done. Although I don't really understand why.