Why was Telegram's CEO arrested?

Depends on what network you read:

SimpleX: To get user data

Nostr: To censor

Farcaster: Crackdown on crypto trading

Bastyon: Israeli data breach. Blame the jews!

Twitter: They are coming for Elon next!

Lens: Must be evil capitalism. I paid $10 of Ethereum to type about money being evil.

Telegram itself: He must have done real crimes. We gotta stop crime right?