We have 'freedom of expression' and case law, but these things end up having to go to court, so I think it being written in a constitution would be better.
Writing things in a constitution doesn't save you from having to litigate them; the US constitution is constantly subject to litigation.
(Not sure how true that is of non-anglosphere countries, though. There's occasional German constitutional litigation, but it doesn't seem quite so critical to politics there)
(Not sure how true that is of non-anglosphere countries, though. There's occasional German constitutional litigation, but it doesn't seem quite so critical to politics there)