Doesn't mean that the server operators could. Think Mega (the new version of MegaUpload): they have these hash/fragment parts in the URL which aren't sent to the server and so you can send links around but Mega can claim they can't read anything because nobody gave them the "join" link to the data they host
But that's not what Telegram does and so they might reasonably have to implement automatic scans if there are an oddly high number of crimes being coordinated on the platform. (Sarcasm coming up:) It's really strange this would happen after they said it's for privacy nerds and then never implemented encryption for any of the useful/standard features
If anyone can access the data, it's not encrypted in any meaningful sense.
If you have access to some data, the government can require you to share it with them. But if you can't access the data due to encryption, the government can't force you to create a backdoor to access it. At least not outside truly extraordinary situations.
