Go to any coffee shop in Palo Alto and Menlo Park, and you're bound to see students and tech workers sitting alone, typing away on their laptops. Even in LA, you'll see people editing videos and posting stuff on social media.
I think it's perhaps very American to go to cafes alone, especially if you are going there to get work done. Anecdotally, I had a French tennis partner back in 2022. One time, after our match, we went to a neighborhood cafe to chat and talk about life. He remarked to me how strange and foreign it is that Americans work so hard. He finds it stupid, even off-putting, that people work in cafes, which to him is a place to relax and socialize. He used slightly stronger language than stupid, so I didn't have the heart to tell him I plan to work in a cafe later that day. Maybe it's just a cultural thing.