This may sound simplistic, but I think you want to find the plucking technique that is most natural and comfortable for you.
I'm getting older....past 70....and have some pretty significant hand problems. I'm also self taught and don't have much technical training, so for me it has been pretty much what I could pick up from others and discover on my own since 1964.
I play mostly blues of all styles these days, along with old rock, Memphis style R&B, and a minimal amount of funk. I find myself using root / octave fingering effectively in these genres. Especially in walking transitions. It's definitely a fundamental in my style. It is most natural for me to do it with my forefinger and middle finger.
My best advice is to try the various suggestions here, find the one that is most natural and comfortable for you and spend some time with it. If it becomes a natural technique for you, doesn't cause injury, and works for the music you're putting out, it ain't wrong.
Hope this helps.
Koog