http://complice.co runs pomodoro chat rooms with webcam video, there is a private group I joined there which always has people on, and a few public ones which often do. I think that's the kind of thing you're looking for.
I'm also in a great Discord group which is a text and audio co-working space: https://davidseah.com/virtual-coworking/
I also use FocusMate for more structured sessions to keep myself accountable as then I have an appointment to show up for e.g. to kickstart my morning. Looking forward to seeing what features they add as they grow.