And how else is scraping going to happen? The traffic is already encrypted, only party that can 'scrape' at that point is the app/site itself. And if you don't trust them with not doing that you shouldn't trust that they wouldn't use the keys they already have to decrypt the content neither
Encryption of public rooms can help prevent mass scraping of content, they still have to join to get keys.
And how else is scraping going to happen? The traffic is already encrypted, only party that can 'scrape' at that point is the app/site itself. And if you don't trust them with not doing that you shouldn't trust that they wouldn't use the keys they already have to decrypt the content neither