The article doesn't say whether there's a medical exception. Not everyone can get the vaccine; having that cost your job is both heartless and (probably) illegal.
And let's not forget that people with natural antibodies are being fired from their private sector jobs too. We seem to be focused on measuring output rather than outcomes. Other countries are giving recovered people the same status as the vaccinated since they have the antibodies. But I guess that makes too much sense...
Everyone (who can) should take the covid vaccine, regardless of their antibody status.