The Hill does same and adds quotes from Rand Corp analysis. (Though I could be wrong, I imagine editors there might have a similar policy as they do seem to strive to report politics in a non-partisan fashion and I don't see any of their reporters on cable TV news.)

New York Times reinforces policy prohibiting reporters from appearing on partisan cable shows like Maddow

By Joe Concha - 05/31/19 09:29 AM EDT

[....] According to the Times' handbook of Values and Practices for the News and Editorial Departments, staff members should avoid shows that "emphasize punditry and reckless opinion-mongering." 

Staff members "may participate in radio, television or Internet interviews or discussions, paid or unpaid, that deal with articles they have written or subjects that figure in the coverage they provide, edit, package or supervise," the public document reads. 

"In deciding whether to make a radio, television or Internet appearance, a staff member should consider its probable tone and content to make sure they are consistent with Times standards," it adds. "Staff members should avoid strident, theatrical forums that emphasize punditry and reckless opinion-mongering." 

The report comes as journalism in the U.S. "has gradually shifted away from objective news and offers more opinion-based content that appeals to emotion and relies heavily on argumentation and advocacy," according to an extensive Rand Corp. analysis released last week. 

“Our research provides quantitative evidence for what we all can see in the media landscape: Journalism in the U.S. has become more subjective and consists less of the detailed event- or context-based reporting that used to characterize news coverage,” said Jennifer Kavanagh, the lead author of the report.

Kavanagh also serves as a senior political scientist at Rand Corp. 

The Hill has reached out to the New York Times for comment.