The law doesn’t make that distinction, though. ‘Untruth’, falsely claimed’, and ‘lied’ are all the same under the law. The only thing those laws care about is whether your words were true. If I call you a liar in a headline and I can prove you actually lied, you have no case.
Weasel words don’t protect them from lawsuits, it’s just another part of the degradation of journalism and the fact that whitewashing and softening their language gets them more clicks & eyeballs, because it’s less likely to offend people who disagree.
With public figures, the bar to meet slander/libel includes that it must have been done with ‘actual malice’ – not anything different about which words were used.
The bar for bringing such a case is even higher for public figures than private people, but it’s still not about the word ‘lie’ vs ‘untruth’.
If you’re aware of a single case where synonyms like that mattered, I’d love to know.