They did amplify, or I wouldn't have learned about them. Twitter does seem to be trying to keep gender-critical viewpoints secret, but covertly, as they make it really easy to get banned for "hate speech" when you engage in gender-critical speech. The same for other topics that people label as misinformation, such as sharing the actual statistical results from vaccine trials. I never cared about the statistical results until people got banned for sharing them, thus Twitter indirectly amplified.

That is a ridiculously tortured argument. The censor not extending his reach to outside venues doesn't make him any less a censor.