The article makes an important point about 'stealth' that is not being acknowledged in the broader trans debate, even though it sits at the heart of it. Firstly there is a very small class of trans identified men who, either by genetic disposition or early medical intervention, do indeed pass, and secondly there is a much larger class of TIMs of whom it is demanded that we treat as though they pass -- that somehow they could be taken for 'masculine' women, even though they don't. In both cases that deception is being used as justification for law breaking.
With respect to the specific case there's a tension in the law which has not been noted in the media discourse -- statutes to protect against sexual harassment, sexual assault and rape are enacted mostly for the protection of women against men. That's obvious as the great majority of perpetrators are men and the great majority of victims are women and surely laws would look different if the only concern were violations by men against other men.
However their perceived (and effective) legitimacy depends on them being universally applicable, ,i.e. everyone irrespective of sex has a right to sexual autonomy, privacy and to be free from violence or coercion. In this story the tension is that if the case were transposed to one where the perpetrator were male and the victim were female it would take on a more sinister tone. It's perfectly reasonable to make the argument that some of the perceived harshness of the ruling is necessary to maintain the seriousness of the sex by deception charge, because that seriousness serves to protect women in other cases.
Likewise its perfectly reasonable to assert that going stealth to access women spaces and services is more serious than just 'wanting a place to pee'. This is because predatory men use deception of all types to get access to women and it should not be normalized.