You're right, it's a lot. But you're also missing something important (like most people here who compare it to products like Cragislist). You're thinking about

You're right, it's a lot. But you're also missing something important (like most people here who compare it to products like Cragislist). You're thinking about it as a service that needs to be run. But Twitter is not an open source project. Twitter is a public company where they need to make share holders happy. That means they HAVE to grow Revenue year over year. At that point you start hiring people just for that reason. Most employees were not hired to run the business. (for example, if Twitter wants to grow its current revenue by 20%, next year they need to roughly make $1B more than what they did this year). BTW, under Musk the pressure to grow revenue is going to be even higher, despite his plans to take the company private. He has plans to triple revenue in like 3 years. Good luck to whoever stays there...