This didn't happen as part of a crash. In fact, I'm not sure what might be the reason. I just looked down and saw this while riding on a sunny day. My bike is always in my room and I live alone. I sit on my top tube from time to time during traffic light waiting. I sometimes descend on top tube. The frame is 23000 KM old. Always by 68-72 KG me. I had crashed before but never hit top tube.
That's pretty bad. No one here can tell you the risk of it actually breaking. What can be said is that it were to ever break, odds are it would happen at some outlier moment of extreme stress on the frame, such as unintentionally hitting a bump on a fast descent. What I would not do is make any assumptions that in any scenario where it broke, you'd get meaningful warning in addition to what you already have.
Canyon has a crash replacement program. The world is more pinched for components than frames right now, so they may even have frames to send. It would be wise to look that direction.