Why would they be? I'm not being smart - this is the genuine way to approach the problem. At some point you started with no protected classes and if there was

Why would they be? I'm not being smart - this is the genuine way to approach the problem. At some point you started with no protected classes and if there was a reason that was considered good enough by enough people, then the list was extended. So if a group in society/legislative branch thinks there's a reason to make the change, the onus is on them to justify it and convince enough people to join that opinion. So if you want a genuine discussion on the topic, you should start with a strong argument about why these views should be a protected class.