Yeah, intimidation is there for sure, but if you think about the why, it becomes a bit darker. The entire republican world view is built on kicking down, blaming others, whether it's blacks, immigrants, anyone slightly to the left on the political spectrum.
Think about it. In order to so rabidly support taking away social safety nets, health care, and basic human rights from entire demographics, you need to believe that they are less deserving, less human. The only way they can hold onto these beliefs is by convincing themselves that everyone gets the same opportunities in life, and that the poor, and the sick, and those with different lifestyles, are only that way because they're lazy, or they've made bad choices. If they were just smarter and harder working they would have gone to university and got good jobs and been upper middle class and they'd have nothing to complain about.
If the BLM movement is allowed to be heard, it could lead to a global admission that their concerns are valid, and that's a big step towards humanizing one of their favorite scapegoats. And from there it's a slippery slope to human decency, and once a sickness like that takes hold, it's the end of the modern republican party.