No it should be based on what you want to accomplish. For example a friend was running some MCMC procedures while editing his manuscript. He had 6 cores and 12 threads. I advised him to run 4 chains on 4 threads so that he had two real cores still available for interaction while editing the manuscript.
If he had run 12 threads his machine would have been unusable for editing. Even if he’d run 6 threads it would have been no interactive because of the 12 hyperthreads only 6 can run at any one time.