As a general reminder, which IB classes your school chooses to offer can make a huge difference in whether this is a good fit for you. And it makes a big difference in what the IBD program at one school looks like versus another. While most US schools offer this as their most academically challenging path, there are also ways in which it can be much more accessible to less driven students - but that’s rarely the student profile for which American schools design their programs.
Some schools do a better job of offering more in the way of advanced math and science in their IB program but the "balance " required by the degree will always make it hard for students to double up on classes in their area of interest. I agree that overall, in most places, this may be a harder sell for an advanced STEM kid.
Overall, this is great prep for college though. Very well thought out, regularly updated by educators around the world, and comprehensive.