I love this post! I’m a postdoc in the social sciences, and I agree with all of it. I went to a small LAC for undergrad, an Ivy for my PhD and am doing my postdoc at a well-known public research university in the Northeast.
I really love when you note that 1) crucial research for undergrad can be performed at an LAC department with good facilities and 2) the exact major doesn’t matter as long as you are taking the prerequisite courses.
While some faculty members may enjoy working with undergraduates and give some or many of them time and resources - it is absolutely true that they are not there for undergrads, in that it is not their primary job or task to educate undergraduates. Undergraduate education takes a back burner to generating research money for the university and educating and advising graduate students.
@dadof1 didn’t say that undergraduates absolutely cannot get good mentorship or research opportunities at large prestigious research universities. He simply said that the faculty at a place like MIT or Harvard have running research laboratories and getting grant funding as their primary purpose, and advising and teaching graduate students and postdocs as their secondary purpose. Having gotten my PhD at one major research university and currently doing a postdoc at another, I must concur. There are some faculty members, of course, who are excited to work with undergraduates and find a way to work it into their time (just like there are probably a few LAC professors who are deadwood and not up to date with their fields). But unfortunately, these professors do tend to be the exception to the rule.
And it’s not really through any fault of their own - it’s the way the jobs are structured. For example, my department in grad school was 80% soft money, which meant that faculty needed to fund 80% of their salary through grant funding (most from the NIH). Many large research universities work this way in their social science and natural/physical science departments. The way they hire and retain faculty promotes this, too. You are hired on the quality of your research record, not your teaching; and you are tenured and promoted on your research record, too. Publications are the currency of the field. Our provost flat out said that teaching plays a very minor role in the tenuring of professors, and quite frankly, many professors find ways to buy themselves out of teaching (particularly teaching undergrad classes, which tend to be time-consuming without having the benefit of being a test lab for new ideas and projects).
That’s not important for undergraduates, though. Undergrads don’t need to be publishing at the most important journals in the field; they just need to learn the basics and have a mentor who can foster passion and intellectual curiosity in them. (And this may be field-dependent, but I have absolutely seen posters and orals at meetings given by LAC professors. In fact, the person who had the poster space next to me at my most recent meeting was from Bates College, and we actually had a little chat about teaching at a small LAC because that’s what I would like to do, since I love working with undergrads.)