Sure, all of these are examples of journalists leaving for ideological or ethical disputes with their employer.

For her frustration with liberal bias: https://www.politico.com/blogs/media/2014/03/sharyl-attkisso...

For a feeling that the paper is blocking his investigation: https://www.cjr.org/q_and_a/paul_watson_may_be_the.php

For disagreement about Israel: https://www.aa.com.tr/en/politics/cnn-anchor-resigns-after-c...

For concerns about corporate interests: https://www.opendemocracy.net/en/opendemocracyuk/why-i-have-...

For feeling that he cannot write about Sheldon Adelson: https://www.salon.com/2016/04/27/journalist_resigns_after_ba...

I didn’t go too far back, but heres one from 1998, for disagreement about revealing personal details: https://www.latimes.com/archives/la-xpm-1998-sep-30-mn-27898...