I'd add Microsoft and drop Facebook, personally, but... yeah, the first part is kinda fair. That said, the second part is wrong. It was no trouble at all to jump from Amazon to Google Seattle when I felt the time was right. My desk at the office (if you remember offices from the pre-pandemic days) is less than two blocks from my original desk at Amazon.
Facebook and Google both have multiple offices around Seattle. I wouldn’t be surprised if Apple or Netflix were interested in hiring in Seattle either.