"Some of those who are being asked to return were laid off by mistake. Others were let go before management realized that their work and experience may be necessary to build the new features Musk envisions, the report said citing people familiar with the moves."

That second sentence, those employees, should tell Musk and Twitter to go f-themselves. To be thrown away because the child billionaire paid too much and has to cut costs asap and then asked to come back because there's a knowledge or skills gap thwarting the pushing of new features is Twitter's problem not that of the employees fired/laid-off.