False equivocation. This did happen but Twitter promptly banned this and variants [1]. Parler is failing / refusing to moderate.
[1] https://www.theguardian.com/us-news/2021/jan/10/hang-mike-pe...
[1] https://www.theguardian.com/us-news/2021/jan/10/hang-mike-pe...
Expecting any potential competitor to instantly achieve perfect moderation seems like a perfect way to entrench FB, Twitter and others as the de-facto public square.