If "claims" is the problematic word in that using it is inherently perjorative to the claimant, our judiciary is in real trouble.
It is entirely standard parlance to describe a thing that somebody has said. It may imply that what is said is untested, unproven OR, in certain tones of voice, doubted or disagreed with, but none of those usages (including disagreement) can sensibly be said to be derogatory.
Unless of course, it is now inherently 'perjorative' to any speaker not to accept wholeheartedly whatever they say immediately and without the slightest application of critical thought. In which case IPSO has just ruled against the questioning of anyone about anything, as well as putting across any conflicting alternative narrative.
I'm not quite sure where they think that leaves journalism and the fourth estate, but what a fascinating conversation that would be.
Side note: Nice article by Gove but feel he could have shortened it considerably by availing himself of the answer given in Arkell v Pressdram.