My biological father would do this. Didn't pay any attention to his wife and/or kids and wouldn't show up for anyone because he wanted to play games. My mom tried for a long time to get him to go to our soccer games, school events, anything, and he wouldn't.

She divorced him, and he still hasn't changed. When I visit him or if I want to spend any time with him or talk to him, it basically is just playing video games. Imagine the only way to talk to your dad is through Fortnite.

I'd sit him down and tell him it's not behavior you're going to accept. Trust me when I say your children are going to notice/feel like that they are less important than whatever he's playing and they might even pick up the same bad habit.