If you don’t like a family member and do not want them to get any of your estate that is fine. You can state a person should not inherit or is left out of your Will on purpose. However, you should not rattle off a list of reasons why you don’t like that person or you feel they are unworthy. That can get your estate in trouble.
Once your Will is executed it is a public document, and bad-mouthing a person in your will can be problematic. THIS IS NOT LEGAL ADVICE: just because in Beckenhauer v. Predoehl, 338 N.W.2d 618, 215 Neb. 347 (Neb., 1983) and In re Estate of Jameson (N.J. Super. App. Div., 2016) it was determined that the estate was immune from a defamation claim, the estate still had to defend these written statements in court. The estate went down in value and the estate was not distributed as quickly as it could have been. Also, these are not your situation and just because a case has been decided one way does not mean that your situation would be decided in that same way.
Please consult your lawyer to find a way that a family member can be disinherited without creating problems for your estate. Possible solutions include creating a trust or by adding a line about why a person is not included that would not be considered defamation.