You find good friends whenever you happen to be in the same place. Your personalities are compatible, and you like to hang out together. You had to go to some place that is a shared interest, after all, to meet that person in the first place. Like a local bar, or a bowling league, or whatever.
Your workplace can be a source of good friends, but people aren’t there based on shared interests, they are there because someone pays them all to be there. So the chances that you find someone compatible enough to want to spend time outside of work is slim, because you are not there out of any particular shared interest other than your career.
The real problem is that the amount of “third places” (like bars and bowling alleys) are decreasing. People spend so much on their housing that they can’t afford to go somewhere else to socialize, and are much more likely to just stay home and interact with their collected virtual friends online.
And also the fact that so much of our work is remote now. I am fully remote and my “team” is spread out worldwide. My work “socializing” is limited to asking people in Southeast Asia about the weather 5 minutes before the 10 pm (my time) meeting starts.