I don't think you will find a single person in the discussion who thinks an employer should stand by if one employee behaves inappropriately to another. They should be told what is acceptable and if necessary be disciplined.
But it's not really up to other employees to make people feel warm fuzzies "welcomed and safe". They need to have a professional atmosphere in the workplace. We aren't actually obliged to like other people we work with. And we aren't required to approve of them either.
What people who love this stuff don't seem to realize is that if you begin to push on one side, you are alienating the other. If you are telling your employees who are traditional Muslims, or Orthodox Jews, or Catholics, that they need to approve and accept everyone elses lifestyle, or make them feel they need to be seen at particular kinds of work events, etc, you are then making the space uncomfortable for those people. They do not feel welcomed or safe or accepted.
A big company can have hundreds or thousands of employees. Many will have very different belief systems. Some of those actually have very different values that oppose each other. There are belief systems that believe anyone who eats meat is morally culpable. That people who use birth control are making a big, ethical mistake. That it is ok to be part of a thrupple, or use prostitutes. That sex is only ok for procreative purposes. That whiteness should be banned. And many many other things.
The only way for all of these people to get on in a workplace is to keep a certain kind f professionalism, and not expect that others should approve of any of the things you believe or do in your life outside of work.
This type of environment can actually be surprisingly effective at building relationships between people who have vastly different belief systems. But as soon as you have some of those people allowed to start telling other people that their beliefs are bigoted or wrong and they should be reeducated, that all goes tits up. It doesn't even matter which group, no one likes being the target of propaganda at work.