Website, you take your own safety precautions to make sure everything is encrypted and not traceable back to you.
Telegram you rely on a second-party keeping your information safe. Sure you can use virtual phonenumbers, burners and so forth, but your signal can always be triangulated, there's no escaping that.
There is always a risk with everything, if you are ready to face the consequences of your actions then I would say it does not matter.
If you are not, stay out of the game, there is no 100% safety for either of us, just slowing down the process of being found or to low profile that it is not worth the chase.
This is only my 5-cents.