Except it is not an argument. I didnot try to prove you anything. Maybe I misunderstood your older messages, but it seemed to me like you used and made assumptions about delta chat without having read the faq before (you posted a channel link on the internet and expected your profile to be 100% private). I just explained what is the current situation of Delta chat, why you are receiving spam, and that there are other solutions (RSS) which are actually far better for what you are trying to achieve (announce your blog-post without being contacted back).
I am ok there are still holes in Delta chat, I am not defending Delta chat, I’m just explaining the current technological situation.
I highlighed the problem of spam via the “Share contact” feature (linked to your problem) at the end of Is spam on Delta Chat a known problem? [subscriber spam towards the broadcast channel owner] - #15 by lucarne
Delta chat is still being worked on, and we hope it will be better in the future.