I think saying that a computer science education is a way to learn "abstract thinking" is a useless simplification, given that any undergraduate degree involves some amount of abstract thinking. Surely a bootcamper is more prepared to work as a software engineer than a psychology major in over 50% of cases (all other things being equal). So the comparison between certain specific majors and bootcampers is much more minute.

Consider that at any major accredited university or college with programs in computer science and software engineering usually these two degrees are separate. Some study computer science and some study software engineering. Computer science as a discipline entails many fields that are unrelated to web development in any way, just as there are fields of math that are completely abstract and have no relation to reality. So, given that a web development role would technically be a form of engineering, you need to strictly compare interviewees with software engineering undergraduate degrees with those coming out of bootcamps without the same degrees, and also compare in-industry experience, age, and every other factor in a controlled way.

In any case, the data from a study like that would be inarguable and it would also be uninteresting. It might hurt some people's pride to see that a 6-month program can outdo a 4-year program, but it is true in some cases. Look at places like Digipen and Full Sail University which also teach programming. It was not at all uncommon a few decades ago for programmers to drop out of high school and be successful. What you will find, from responsible adults, is that no one would advocate this path. So it shouldn't be surprising that almost everyone will advocate the benefits of education.

It would be easier to compare a specific bootcamp with a narrow set of courses from a CSSE program, and it would be more of an apples-to-apples comparison.