This has nothing to do with privacy either. First of all Telegram is not a private messenger. Secondly, this is a about public forums and groups called Channels. This has nothing to do with backdoors eithe. They are simply asking them to do moderation on chats they already have access too.
Telegram has full access to this data and knowingly ignores child pornography and other criminal activity. If Facebook did such a thing for years you'd be screaming right now.
Telegram chats are not encrypted by default, only Secret chat is which is not synced to Desktop and only works on one-to-one chats, no groups.
Because almost all data is encrypted. They don't even know who is messaging whom. How can they be charged with crimes they didn't commit? They don't know what their users are using the messenger for, so they can just deny everything.
No you can't unless you have access to the phone itself. It's impossible. You clearly have no idea what you're talking about.