Yeah, sounds like it was a lot of people stomping their feet and didn't want to come back for in-person work:
"The attorney's message comes after Musk announced he'd require employees to be in the office 40 hours a week, eliminating remote work. The attorney believes this is a "fundamental change to our employment contracts," they wrote to the Slack group consisting of over 2,000 members. "I do not, personally, believe that Twitter employees have an obligation to return to the office. Certainly not on no notice."
Considering Twitter was an in-person shop before the pandemic, I seriously doubt if there were material changes to contracts that actually allow what this person is complaining about. If there were, lots of lawsuits would have already been filed against Elon by the employees.
Chalking this one up to someone didn't want to come to the office, so is quitting instead. Trimming more of that fat.