You might think I’m just being picky, but my take is that you may be able to imitate the tone/sound, but I’ve never been able to duplicate it, even with the most thumpy rounds.
That said, the whole world of flats and bass strings in general has changed so much over the last 20 years, and the line between flat and round is not so easily drawn now — evidenced by the development of flats like Thomastik flats, EB cobalt flats, and then rounds that are compressed, rolled, etc. So in that sense, you have a point.
But if there is a round wound string that can duplicate the sound of say, La Bella DTFs, I’m not aware of it.