This phenomenon makes sense though, those who chase the prestige of a "top" MDPHD are likely to be historic prestige chasers, going to these top colleges. In the end, any MDPHD will likely conduct amazing research regardless of where you go.
If the hiring of MD/PhD researchers in academia has any semblance to PhD hires, going to top MD/PhD programs is quite important for someone wanting to go into academia. The old saying in academia is that you will never teach somewhere higher-ranked than your grad school and/or post-doc program. Science is becoming increasingly collaborative and nowadays, it's not enough to be a research genius. You need other top-notch researchers around you to work with in order to get truly phenomenal results. So in my opinion, doing a PhD in a non-top-ranked program isn't worth the time.