In principle, I agree with you -
At the same time, people are more than their sexuality, and people are bigger than labels - even the ones they proudly choose to put on themselves. Sexual identification is just one facet of what comprises a person and what they do with their days, or achieve over their lifetime, and a magazine on the level of UK Elle is unlikely to treat the issue with much sophistication, which is why they're better off focusing more on fashion with a side-order of social analysis, rather than trying to convince us they're got revolutionary content in their cover story.
Plus, it's possible to be LGBTTIQ+ and be an absolute bore.