Yes, those highly-connected nodes could easily kill the network... if they all coordinated to leave at once. Which is a real risk here, because of how high-profile and controversial the issue is right now. But normally, they're just as glued to the network as everyone else. Perhaps even more so, because...
... they aren't creating content for fun. They're creating it to make money off the audience. So they have to stick to where the audience is.
People with blue check marks would like to think they're special and valuable to the platform, but they're not. At this scale, they're a commodity too. They play a different role on the platform, but for the platform, users with different roles is just what makes the whole thing tick and print money.
