Isn't this a consequence of Telegram's actions?

It was their decision to become something bigger than a simple messaging app by adding channels and group chats with tons of participants. It was also their decision to understaff content moderation team.

Sometimes the consequence is a legal action, like the one we're seeing right now. All this could have been easily avoided if they had E2EE or enough people to review reported content and remove it when necessary.

Telegram started 11 years ago. I know the term has been diluted for ages, but it still rubs me the wrong way to use the word startup for decade old businesses.

A startup wouldn't need hundreds of people, they don't have millions of daily messages yet. Only successful businesses like Telegram would.