My partner and many of her friends did IB in the late 2000s and every single one has trauma from the workload and culture of expected achievement and it doesn't seem to have benefited their careers at all. (I did Running Start instead, a Washington State early college program, and had a very positive experience)

I took the IB and IGCSE. Trust me, I almost killed myself during the IGCSE. No such problems during the IB.

*Edit: I payed basically nothing for the IB diploma in Germany, it was from 11 to 12 grade, so not the "IB learners" thing people do in primary etc. The work load was a lot and I was taking college courses on the side, as well as creating a music portfolio outside of school, and applying to American colleges. But I managed pretty well. No trauma from the work-load for me. YMMV though, some people here seem to report very bad experiences. I should note that the IB was much more work than my first two years of college.

For context, I was very dyslexic (but had compensated pretty well for things like reading and writing) and was very academically interested, but the IGCSE curriculum is the most anti-dyslexia and anti-academia curriculum you could take. It basically tries to make everyone into good little government puppets. All the exams are about short-term memorization and surface-level understanding, the math course is laughably easy, drama is a farce, and English is genuinely going to make your kid dummer.

The IB is also very flawed, when I was taking it, and also today, as I am regularly told by a friend who teaches the IB and grades IB exams for English Literature in Germany. But for me, back then, as a student, it was infinitely better; suddenly I was independent, could pursue things academically (except in physics, the IB doesn't do the sciences very well IMHO), etc.

But what I have come to realize is that this was very influenced by my IB teachers (same school as where I took the IGCSE though, teachers just had more freedom, were more qualified, etc). Ironically, they often complained about the IB and not having enough flexibility, the exams not being representative, etc. But the IB was still leagues better than the IGCSE (or, god forbid, the Abitur).

I took philosophy, for example, from a wonderful, wonderful teacher, who taught us everything without a text book. Instead, she used her expertise (a doctorate from upenn) and the original texts. Everyone in the class got at least a five, most people who cared, got sevens, myself included. To this day I have not had a better class (we were, admittedly, only five students, which does help).

I don't think the IB is intrinsically good or intrinsically bad, unlike the IGCSE, which is meant to brain-wash you, and completely and utterly destroy those who don't want to be brain-washed.

The thing with the IB is going to be the teachers and school. Also note that some of the exams, back when I took them, were kinda random. Like getting a seven (the highest possible grade, fyi) in English or German Lit was a little unpredictable. I can only hope that's improved.

For context, I also improved hugely academically when entering the IB. I was already interested in higher education, and was taking college classes during the IGCSE (because it sucked so much), but was still roughly a B minus student. Going into the IB I became a top-scoring student within one semester. I graduated with a 43/45, which I don't think my IGCSE examiners nor myself in 10th grade would have believed. I have a lot to thank my IB teachers for, and ultimately I am very glad a took the IB. CAS ducking sucks though.

I dont know about the american/uk system, it might be better there. I went to the international line in europe and it was a complete disharmony between how the teachers thought they should teach and what kind of teaching IB required. Theres also a lot of shady stuff with IB, like you can basically pay for an expensive tutor and completely coincidentally they will teach you the exact right knowledge to get a good score on the exams. The problem with this is that if the exams dont have a certain subject in them that year, the tutor wont teach that. Basically if you want your kid to be a successfull businessman or whatever, and you have a lot of money, 100% send em to IB, but if you want them to think for themselves, theres very probably a better option. Once again this mainly applies to my experiences in europe, there are many countries here where IB is a joke, like in hungary nobody goes there cause you have to pay, get worse education, and dont really have any oppurtunities going forward with it. Id say go ask other people but some of them will be absolute IB shills for no reason, and others will say its the antichrist itself. Also from what i understand, you do have to pay for education in uk to get somewhere right? Then id guess IB isnt that bad cause youre paying either way for school.