I am 25 and a few years out of college. I currently work at my first job out of school and feel passionately about the question you pose. Here are my two cents.
Do something you think you might love, because if you are an insightful, realistic person with modest material desires, more money will not be important to you in the long run. I make around 50k a year, I am single, and I have more than enough money to put 16% away up front, cover my essential costs, and have enough money left over to do a reasonable amount of "living" (ie- happy hour, concert, travel...). Also, where you invest in your passion, you may or may not make more money but you are likely to do fine if it is something you don't mind putting all your energy into.
I've found that I have only been motivated by the promise of the next yearly raise in a limited capacity in my job. It sustained my initial interest but it wasn't more than two years that I was yearning to be doing something I was passionate about and because I feel that my current job is not that profession, the money has not kept me motivated in itself (I have a job where I could potentially make over six figures if I chose to invest the effort and time).
All that being said, I completely understand that each person is different. I work with people who are fully motivated by the promise of a long career and a lot of money. They are not hung up on whether or not the job they are doing is meaningful or fulfilling. Knowing yourself and whether or not you think you will be motivated by money or eventually determine that you need to pursue a passion will make a big difference in how you should choose. Hopefully your job offers you a little bit of both. Your personal values about material possession are also going to specific to you (but we have always have the choice to understand that "things" are just empty placeholders that don't provide much value). My two cent is from the perspective of someone worrying about themselves and I haven't yet had to think about a family or the future ego effect that a specific salary might have on me so I think you are right in posing that question to the middle-age folks.
Hope this helps in some way.