I guess that’s on a PC? Or isn’t there any iOS or Android app on your smartphone which is either showing in-app adds or just simply hooked up to adtech by trackers?

Yep, decrypt … export elsewhere to csv txt json … encrypt

While true I don’t get why this is long known and also news at the same time.

For Signal Backup tools for example this isn’t a bug but a feature and the only way to make long term archival of chats possible.

Thats just a user frontend showing your personal view of things . Nobody outside Google knows for sure if they really remove it from their end. All we know is they COULD keep a copy for themselves.