Had this problem with both Overwatch 1 and now Overwatch 2. I press play, a black screen opens and then it closes. In task manager, only the Overwatch Launcher application comes up. Tried all the advised steps I could find which include:
Update your drivers and operating system
Reset your in-game options
Update or temporarily uninstall any security programs / adding an exception
Delete the Battle.net Tools folder automatically rebuild outdated or corrupt files.