I have a friend who is a cloud architect at a big-4, he is making a little more than $300k in total comp in NY (base is lower, a lot of RSUs etc), but he is more than just an engineer.
He has a friend at another big-4 in NY, also a cloud architect, he is making $400k
I think that the $1 million package is incorrectly calculated. This is perhaps the total package for 2-3 years, including signing bonus (vested over a couple of years) and RSUs (vested over a couple of years)
Annual total compensation for any big-4 Sr software engineer with a lot of experience in SF I assume is around $300k and can get up to $500k if you are really good.
I don't know of anyone who is making $1 million a year, even senior directors at big-4s. Perhaps if you are a Phd who worked at Google cloud / AWS / Azure for 5 years, wrote their software, talk at cloud conferences, wrote "Cloud computing for experts" type of books and published a seminal paper on distributed computing, then perhaps you will get a total compensation nearing that.
If you are just a cloud architect at a big-4 I think the lower part makes sense in total comp, the upper bound sounds completely ridiculous. I have friends who got offers from Amazon and Google for very, very senior cloud positions, way more than "just a cloud engineer", and the total comp is around $300-$400. If the stock goes up though, then the RSUs might be worth much more.
If LinkedIn / Facebook are offering engineers an annual $1 million I'll be very surprised.