The problem is that carbon fiber doesn’t hold up well to the beating and twisting of the typical steel on aluminum seatpost issue.

Twist and pull and you could damage your frame.

Even if you cut it out and drill, I think the chances of you damaging the inside of your seat-tube are nearly 100 percent.

I like the soapy water idea. Or possibly heat, but not hot. Leave it in the sun in the yard. Bring it up to to maybe 100F. Not the heat wrench, just a little more pliable.

I’d probably make a slurry of intimate lube, soap, and water and find a way to get it into the frame. I’d use really warm water for this.

If it ever comes out, even if it’s intact, I’d never use the seatpost again. It could be the wrong size, marked wrong, or have some defect that caused it to jam.