> if I have a belief that my employment should make a positive change in societal issues, how could I work somewhere that I believe contributes to making things worse?
Why the binary presentation, though?
You can make the world better by doing a single thing well and respecting your customers (and their all-kinds-diversity) while doing it. Even if you're not directly contributing to BigIssue by doing it, the people who are presumably need to be able to count on a reliable supply chain that gives them the tools/services/resources they need.
Unless your work has serious atypical externalities, just doing what you're doing doesn't itself make things worse -- it make fail to do the absolute maximum it could possibly to to make one specific thing better, but if that's your focus you should be working on that thing directly. In a reasonable organization there should be a lot of opportunity to put your thumb on a scale towards continually improving all sorts of things-- without inviting disruption and discord --by threading the needle and nudging all the free choices in the right direction and respecting that other reasonable people can have different priorities.
There are an neigh uncountable number of travesties and injustices in the world and finite time and resources to fight for them... but as a society we can't stand strong to face any of the big issues if the water taps aren't flowing, the power isn't on, the communications lines aren't communicating, the spread-sheets aren't spreading, the trash (literal and figurative) isn't getting collected, and whatnot. We have to prioritize, triage, and focus on what we can accomplish.
And someone-- many many someones, in fact-- has to be the shoulders we stand on as our tallest reach for the stars.
Besides, if advocacy was really what people were sold on in large numbers how can we explain the literal order of magnitude compensation differences for rank and file engineering staff at tech companies and tech roles in non-profits? :) I think that asks me to believe that there were many people who's next alternative to a google role was taking a $40k/yr 501c3 job and google was foolish enough to offer that person a mid-six-figure compensation package.