If I had to guess, a "modern" Smalltalk environment looks like what Dynamicland has been doing with Realtalk (Alan Kay is behind Dynamicland and was the individual who came up with Smalltalk on a dare basically). I got to visit Dynamicland in Oakland several years ago and it was friggin awesome!

6 minute overview video from August 2024: https://youtu.be/5Q9r-AEzRMA

I guess they're in process of setting up another space in Berkeley now (AFAIK, the Oakland lab more or less closed during the pandemic)? https://dynamicland.org

So yeah, you might have to be in that "one room" (Dynamicland in Oakland was several rooms) but, that's kind of the co-creating with people in spatial collaboration in essence, or as they term it: "communal computing."