Matt even dunked on DHH that only 8% left automattic, while 30% left badecamp back when they banned politics. Nevermind the fact that DHHs offer was without a timelimit, allowing people to figure out their options. Also the job markets couldn't be more different.
However, I do think a fair amount of automattic employees do not want to leave since their benefits seem actually really nice. Not many companies provide constant pay regardless of your cost of living, so I commend them for that. It could be impossible to find an equivalent job for non US employees, so 6 months pay for leaving in this market is hardly worth it, unless like you said you had plans to do it anyway.
However, I do think a fair amount of automattic employees do not want to leave since their benefits seem actually really nice. Not many companies provide constant pay regardless of your cost of living, so I commend them for that. It could be impossible to find an equivalent job for non US employees, so 6 months pay for leaving in this market is hardly worth it, unless like you said you had plans to do it anyway.