With the exception of libel or promoting the overthrow of government, a columnist can write whatever he wishes. Every newspaper in the country has a columnist.
Whether you love the column he wrote or use it as a Charmin, he has a right to express his opinion. His opinions are his opinions.
With the exception of slander or promoting the overthrow of government, a head coach can close practices, not participate in post-practice interviews, and ban players and assistants from speaking with the media. That happens across the country.
Whether you love that a coach would make a stand against perceived unfair reporting or think he needs to see a dermatologist for thin skin, he has a right to create his own media policy for practices. His policies are his policies.
It is what it is.