@Waitwhat23 And that's the best they have? 
That's why everything has to be a "dogwhistle". To a neutral observer a question in parliament might be raising a potential problem or summarising of a point of political disagreement.
But a neutral observer might then think "well that's a good point, what's the counter-argument?" And that cannot be allowed because the counter-argument is likely to be obvious nonsense. So it can't be a valid concern or even a disagreement, instead it must be a coded attack.
And the other reason is that when (for example) someone holds up a placard that says "decapitate terfs" at a demo and no-one has held up a similar placard about trans people (and if they did then the person holding it would probably be arrested very fast) well then the only way to make it look as if you are still the victim is to pretend that phrases like "biological female" are somehow just as bad. They're a "dogwhistle", see, which secretly means something just as violent and nasty as "decapitate terfs" to anyone in the know.