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...
2014: Sharyl Attkisson worked for CBS for two decades, heavily criticized Obama administration and yet left on "amicable" terms (according to that article).
2020: Bari Weiss (who isn't exactly a pro-Trump Republican) faced "constant bullying" from colleagues at NYT, attacks from them on Twitter and on internal Slack. Less you think it's her personal problem, James Bennet was forced to resign from NYT for allowing a republican senator to publish an OP-ED.
Does it not seem like there was a shift of some sort? Well, apparently Attkisson herself published several books claiming that things have changed:
https://www.amazon.com/Sharyl-Attkisson/e/B001IYXCFM/ref=dp_...