I work at Google because they pay me money that I can donate [1] and I wouldn't work here if I thought that was making the world worse. [2] I left Google in 2017 to work for a startup I thought was more positive than earning to give [3] and then I rejoined later that year after the startup didn't pan out. [4] I'm open to arguments that I should be doing something else with my time!
[1] https://jefftk.com/donations
[2] https://jefftk.com/p/value-of-working-in-ads
[3] https://jefftk.com/p/leaving-google-joining-wave
[4] https://jefftk.com/p/rejoining-google