Yes, detransitioners are excommunicated, ostracized and silenced. The narrative is that they don't exist, were never trans, only detransitioned due to transphobia (ideologues don't have problems holding entertaining contradictory thoughts as long as these all serve to maintain a closed belief system). Any media coverage at all is evidence of transphobia, bias and plots by those nasty gender critical transphobes (despite the fact that most journalists are terrified to run stories that go against the activist narrative).
But more generally, experts such as Cantor and others have pointed out that activists who are transgender come from the minority for whom transitioning worked well, and who assume that everyone is like them. Those who desist (the majority) don't get heard because they don't become activists (nor do most detransitioners: Keira Bell is an exception). The loudest transgender activists tend to be late transitioners who are a different group from those with early-onset gender dysphoria, but tend to impose their own retrospective regret at not transitioning earlier on others.
Cantor explains this fairly well in this clip.