CSAM. That one user sent to another.
And yet, X/Twitter, which can generate it, wasn't taken down.
Political posturing, nothing more and nothing less.
Even if you think Telegram should have been banned: how does it affect YOU what another user sends a different user who isn't you? At the end of the day, you simply aren't affected. FYI, other apps have been used to send CSAM. Facebook. Instagram. Whatsapp. Hell, Snapchat was made for exchanging CSAM. Even Apple's built-in technologies, such as iMessage, AirDrop, and Safari, have been used to view/transmit CSAM.
Meanwhile, nothing's being done about the American politicians who are actually making CSAM (abusing children). So yeah... political posturing.