I'm less and less a pick player, it does have that specific tonal sound, clarity, attack etc. But......so does double thumbing and so does double index fingering and so does tapping.
I think you can get there with multiple paths, but another poster made mention that he/she plays and thinks differently with a pick, I do as well, so it is a useful tool to acquire, but quite of few of the top bassist in the world have trouble with pick playing even if they have the Right hand of God. Tool/Green Day do pretty good for pop bands, and Stanly and Manring seem okay not using them.
I'd have to stick with the old: it's the player, not the method or the bass or the amp etc.
I think some pick players feel a tad insecure, please... do not. I did way back when and it was not really justified, I liked slap like many, but you can pull off some decent stuff with a pick. Still, I learned to groove with the thumb and fingers. It was more organic and physical, a closer connection to the instrument for myself.
Any upright players using picks?
That would be weird.