But if you can't justify why you should study it, study something justifiable until you can.
I tried both. I wrote two R01s that were funded in the early 00's. I was 2 for 2. Unfortunately, they weren't mine, and I didn't have a PhD yet. Also I got a AHA fellowship at that time, so 3 for 3.
I submitted about 30 grants after 2005, everything from basic science to translational. About 70% of these were Not Discussed. None of them were funded.
It's not the justifiably of the science, it's $/scientists.