I think the difference is signal is private, no? Parler people are just airing racist and threatening shit out in the open. I would personally rather it take place in such private online places instead of in front of everyone.
Rhethoric in Germany is already pointing at various WhatsApp and Telegram groups filled with people discussing unsavory topics. Protocols have been published and the groups are not really that private anymore as soon as you no longer know and trust everyone in them. So as soon as the first Signal groups with Nazi policemen shows up, there will be pressure to somehow get rid of those groups...
So what you're saying is you want to have Nazi policemen? I don't understand what your concern is, because they would probably be incapable of performing their duties fairly
No concern, I just wanted to provide an example for what is currently happening in Whatsapp and Telegram (private groups where illegal content got posted, became known and caused the state to try to get rid of those groups and punish members).