I keep seeing men of a certain age riding carbon frames with 3cm of spacers under a ‘flipped‘ stem. Aside from looking awful (to my eyes at least) I can’t imagine the handling is as the designer intended
I think that I must be missing something here; manufacturers supply bikes with a cut steerer. If you want to be a bit more upright then a bit of flippage is the only way to go, unless you want an adjustable stem
Call me old-fashioned but if you want to push the CG forward and get low then move your hands onto another part of the handlebars
Regards
tim-b