I don't think there are any (even far) leftwanting to ban non-diverse representation.
I think it's impossible to ban 'conservative thoughts' because that's such a poorly defined phrase.
However there are people who want to ban religion.
One difference is that a much larger proportion of far right (almost all of them) want to ban lgbtq depiction and existence compared to the number of far left who want to ban religion or non-diverse representation.
It says on the wikipedia article itself
'The horseshoe theory does not enjoy wide support within academic circles; peer-reviewed research by political scientists on the subject is scarce, and existing studies and comprehensive reviews have often contradicted its central premises, or found only limited support for the theory under certain conditions.'
Thing is, under capitalism large companies get significant control over the governments' actions. And large companies don't like not being allowed to be as powerful as possible, holding monopolies.
So you think that because wikipedia guidelines are intolerant of intolerance and don't fit with your personal (bigoted) opinions on trans people that means they are misogynist?