I think it's slightly more complex. Many academic programs have research tracks (dedicated slots for research residents). You can guess what they prioritize.
Many research institutions though want good clinicians primarily, but can equally weigh research background if it seems that person is a rising star in academia.
Beyond that, I had noticed a year to year difference in priorities, often a bit reactionary (if there's some real trouble residents the year before, then the PD may make an extra effort to not make that mistake again), which I found leans more towards favoring stronger clinical backgrounds.
There's also a factor of good clinical but coming from a strong academic med school. That seems to hold some weight too.
I personally viewed research background as icing on a cake. It's pretty sweet when it's there, but if there's no cake to go with it, you're more likely heading for a sugar crash.