It is such a boring waste of time when you have to listen to some new cartridge that sounds awful when it’s new and doesn’t impressed you at all in the first 30 hrs.
no one said that. Most say it starts out great and then gets better. That's what I experienced. You yourself wrote that break in makes sense. I agree with you. It's like a new guitar or a violin. It needs to be played a while before it hits its real potential. You stick with it because you can hear from the beginning that it's a good instrument, so it's worth the effort. Nothing strange about that.
That said, I agree that this thread could/should be more than just cheerleading for the ART9. There's no professional review of this cart available (as imperfect as they often are) so it would be nice IMHO to have some attempts at objective description and comparisons with other carts. I will attempt to contribute to that myself when my ART9 and Doshi phono stage are... em... broken in.