The practical effect of the supreme court ruling has indeed been horrible in cases, but I would lay the blame mostly with the media, and perhaps with the Court for failing to provide sufficient clarity to the media. The actual ruling is so much narrower than the conversation immediately afterwards, with the BBC asking unqualified people if they thought it meant that women’s bathrooms were now only for biological women, when there was simply no need to ask this question - the ruling is clear that it doesn’t say this.

This reporting then feeds the situations you’re talking about. Now, should Starmer have spoken out about this? I can see the argument for doing so, but not from the popularity point of view. The basis on which he could reasonably speak out would be narrow and legalistic, and risks treading on the authority of the Court. It wouldn’t be the resounding pro-trans rally I imagine you might want, because that just plays into the hands of those trying to turn trans rights into a wedge issue.

Online Safety Act

I’ll just point out that, tragically, this is another one of those things which is stupid but popular.