Presumably not every integration requires browser automation, so they might not all be going at once. But they have a $25k monthly EC2 bill, so it's not out of the ballpark.

FWIW, I reliably have 6 puppeteer/chrome instances (headful, even) going on a single box and it's not even at half capacity.

Check out the selenoid project. It’s like a selenium grid but dockerized with novnc, etc.