The DOJ has a slim chance of blocking the AT&T-Time Warner deal, but even that may be enough for Comcast to throw in the towel on Fox
https://www.cnbc.com/2018/07/13/heres-what-the-doj-needs-to-happen-to-win-its-appeal-against-att.html
The Department of Justice has not given up: It's still trying to block AT&T's acquisition of Time Warner (now named Warner Media). And it probably dooms Comcast's chances of buying Fox.
For Comcast it doesn't really matter that the only way the Department of Justice can win is if the D.C. Circuit Court of Appeals rejects the fundamental premise behind U.S. District Judge Richard Leon's 172-page decision. The appeal itself may cast enough doubt on Comcast's chances that it will more formally shift its attention to acquiring Sky rather than the remainder of Fox, which includes the Fox movie studio, Sky India, a 30 percent stake in Hulu and other assets, according to a person familiar with the matter.