Examples:

• Celebrity accounts
• NPR

They all quit over petty disputes with Elon Musk's policies.

But any mature, sensible, or business savvy person would find a way, and work within their constraints.

Why did they fold so easily?

My theories:

• They are all run by inexperienced people who can't handle the smallest bit of challenges in the workplace. Maybe managing a Twitter account is their first job.
• They are all heavily influenced by FBI, and CIA. They are encouraged to just quit.
• They are all managed by the same firm who lacks the man-power to play a chess game with Elon. (Any kind of work that's as complex as chess is too much brain power for them).
• Twitter or a white hat proposed a plea bargain that requires quitting Twitter.