for me, it has always been about trying to find a balance of both. I want my bass lines to keep me happy - which is where the technical pursuit comes into play - but also to keep the audience happy - which is where the taste thing comes into play.
I think experience is what helps find the right balance. Many times I will come up with what I think is a real cool technical part....that doesn't fit the song. At 21, I would "force the round peg into the square hole". At 44, I just find another round hole in another song.
I feel like I have not reached my goal from the musical/technical side yet, so that is what keeps me going, and gets me through the "Root E and A" gigs. It has also given me a greater appreciation for the "root E & A gigs" as I have learned more about musical styles, song construction, history of the basses role in the given style etc. You can't be flashy or technical - in a musically correct way - without understanding the foundation of what that stuff is built on. Since music is my religion, every involvement I have with it is an interesting and positive experience.
As far as the other part of the question. I do not like it when a bass player (or any instrument for that fact) gains popularity WITHOUT respecting the history, style or those before them. I generally tend to have less respect - at any level - for those who are just in pursuit of the material side of what we do. I know I am in a very small demographic with these beliefs, but that's how it is.
I have NEVER equated sales with ability. Unfortunately, we live in a society where people don't "do their homework" and just blindly accept what everyone else is saying as fact. Sheep. In this mindset, most of the people who are true artists go by unnoticed by the masses, and the flash in the pan jokers and charlatans gain notoriety. The karmic result? Many of the flash in the pan guys go away as quickly as they come...and the artists stay around for ever, I am willing to bet that in 100 years, NO ONE will remember Fieldy, or Pete Wentz. Jaco on the other hand? Geddy? Wooten? Those guys will still be remembered for what they did for the craft....