They are at lunch. Why is someone bringing up a new project? Another reason why I take lunch solo.
When I worked in offices, I always did lunch solo. Walked around the city, breathed semi-fresh air and even checked into my local church for a quick prayer & a bit of meditation. I returned to the office totally refreshed.
I am with you. Lunch for me was down time. (I’m retired now.) If I was with others I did not want to discuss work. Discussing what was going on in others lives was OK with me. I too would rather take lunch solo rather than it be just one more hour of work.