How about this?
You can sound meh, bad or good.
When your gear is either heavily eq'd or very colored by design then what you do with your fingers is less important.
When your gear has a wide dynamic range, is more transparent, and your playing has developed so unconsciously you are changing your touch to add different inflection and color note by note then tone is in the fingers.
It's been said here that the original P the single coil '51 or later called Telecaster bass was designed to sound like an upright. Even with round wounds if you bend your index finger so from the second joint to the tip is parallel with the strings that bass will give the fast decay prominent thud of an upright. Get out a pick and you sound like Ron Wood with Jeff Beck. Rotosound roar.
It's okay if we repeat this discussion as new members are joining us.
The trick is as Marcus Miller said, "get your gear then get on with playing."
You have to want to hear the note sound like you want it to. That's not knob twirling its intention.
Doubt this? Play upright. Why do different bassists sound different on the same bass? No graphic eq, tubes or SS, 12"s or 10"s etc. Just touch.