Why? you can already be denied employment for any reason in right to work states and importantly fired for any reason or not...
You say that like it's bad thing.
My entire working life (44 years and counting) has been in either a right to work state or in a non-union field. I have never had sympathy for the "I'm owed a job, whether the employer want's me or not!" whine.
I've worked for a number of employers who didn't have the sense to see my value. In some cases, I was let go for no discernible reason or I walked away and looked for a better job. I wouldn't have it any other way. I don't want to work for someone who doesn't want me around in the same way I damn sure don't want to be forced to work somewhere I hate. I might not like a job, but I have enough sense to appreciate it while I look for another gig.