Most of the web developer world cared about an alternative, just ask any older FE developer after screaming iiiieeeee (6) when their pages failed to render to published standards in it.
For what it's worth, the moment I read the letter I also pretty much assumed it had to be Dave Hyatt. (Source: worked at Mozilla from 2009 to 2020; Silicon Valley browser dev is a fairly small world.)
Hyatt never worked for Google—he's still at Apple as far as I know. Might be that Google ultimately retracted their offer, but knowing Steve, Hyatt would probably not have remained at Apple no matter what happened.
I don't have any inside info here, but I'd be willing to bet Darin Adler was one of those other REDACTEDs. He was an early Safari guy, as well as tech lead for Mac OS 7 and worked at General Magic, so Google would probably have been pretty happy to get their hands on him.
I still think the main one was Dave Hyatt. Ben Goodger (referenced in those emails) worked on V0.6 of Firefox that Dave started. Ben was founding team at chrome just before these emails (see his LinkedIn for dates). Dave was instrumental on WebKit for Safiri. Chrome picked WebKit too. Dave was also that good and was well known to Steve.
I also think parakey was the startup referenced as his other option (Blake Ross and Joe Hewitt)
Hyatt was honestly the first name that came to my mind, and in fact I had to look him up to be certain that he didn't move to Google. I guess I assumed that if it was Hyatt, he'd no longer be at Apple, since it sounded like the person in question wanted to leave, but who knows—maybe Apple got him to stay?
Steve Jobs was obsessed with loyalty, so I figured that anyone applying for a job at Google would be dead to Apple as long as Jobs was there. Hyatt was one of these guys who even Jobs would probably have hesitated to blacklist, though, so maybe it really is him they're referring to here, and he ultimately remained with Apple.
Steve probably needed this team for iPhone Safari. That could explain why he was so pissed. Perhaps just showing them the iOS plans and a some extra stock was enough. Perhaps Google pulled the offer. Perhaps both.
"Sergey Brin and Steve Jobs got into a yelling match over me."
Obviously that's stretching the truth a bit but that would get a lot of attention pretty quickly. Maybe enough to skip the leetcode challenges.