What on earth are you talking about? Leadsom was interviewed...and in said interview, argued that the fact she is a mother perhaps better qualifies her to be PM of this country than her opponent. This is quite clearly a rather bizarre view to hold, and was rightfully picked up on.
The job of a journalist, in any given situation, is to find/report on a story, and to highlight the most relevant and newsworthy story regarding said story. In this case, it was quite clearly, by a monumental distance, Leadsom's absurd view that being a mother makes her a better PM.
In the same way that if Theresa May was being interviewed, and pulled off her face to reveal that she was, in fact, actually Michael Gove, it would be rightfully reported as being the most relevant issue to have come from the story, as opposed to, say, her tax plans.
Journalists are often incredibly sensationalist and talk up stories for the sake of it. This isn't one of those cases, though. A potential future Prime Minister of our country has expressed an incredibly backwards and outdated belief in an interview. The newspaper at hand have, as would be expected of any remotely credible outlet, reported it. What's the problem?