I loved this article and it's honestly life changing. It takes a bit of time to realize how much you're in the driver seat as a candidate. Especially with competing offers, there's no way you should be accepting an offer with less (unless its a small startup) if you have another offering more.
A 5 minute call that can increase net worth by large multipliers is probably worth preparing for. With the help of https://levels.fyi and other salary tools out there, it's incredible how open a lot of this information is. You just need to put in a bit of time and effort.