And no mention of Jaco Pastorius yet. I think he is a case in point. Buzz comments on the sound spectrum that the human ear can hear and it could be argued that Jaco's bass was EQed around the mids. Yes we do like melodies in higher registers. Not many basso profundos at the top of the charts.
The bass needs to go where ever people want to take it. One tune that comes to mind is Weather Report's 'A Remark You Made'. Jaco played that lovely lead line but them seemlessly goes back to holding down the bottom end.
Probably the only reason we don't have any young bass heroes is that they just don't get signed cause that type of music doesn't always sell bucket loads. There arn't many young guitar heroes either, except maybe Matt Belamy. Same reason, not fashionable.
The good players are out there who can take the bass forward but as is the nature of the instrument, and its players, they don't always hit you in the face.