Air taxi First Officer reported an unstabilized approach resulting in a CFTT event in inclement weather with close to zero reported visibility. The First Officer repeatedly asked the Captain to execute a go-around; yet the Captain ignored the requests. Post landing; Captain admitted a go-around would have been the best decision.

Narrative

While on the RNAV approach to ZZZ Airport visibility deteriorated rapidly as the descent into the final approach segment of the RNAV XX. Heavy rain began prior to the arrival of the minimum approach altitude and continued until nearly reaching the field. Visibility deteriorated to the point of almost zero; yet the Captain continued the approach in belief the rain would clear up. At the missed approach altitude I called 'go missed' approximately 3 times in an effort to get the Captain to discontinue the approach; yet the Captain continued his descent into the field. As he continued I continued to called negative contact; 'GO missed'. The Captain ignored all calls and continued until breaking out at an altitude of nearly 200 ft. AGL; which was an extremely low altitude so to the point we were short of the field and well below the glide path. The 'break out' altitude was approximately 300 ft. bellow the appropriate ceiling requirements for the RNAV XX at ZZZ. Upon landing the Captain remarked 'you were right; we should have went missed; I thought we were going to break out just below'. I have never been more afraid for my life and terror than on that approach into ZZZ to the point I feared for my life as the Captain ignored all my pleas to go around. I reported this incident to the training Captain. This is not the first time this has happened while flying with other captains at Company X and the conduct has been reported to the director of operations and chief pilot multiple times and was told to 'not make waves'. The safety culture at Company X presents a serious risk to aviation safety as a whole.