Yes, that’s totally normal. Today was the first day that the 12 Pro Max was actually available to consumers, so today is the earliest that your phone could have been delivered. The 12 was available as of a few weeks ago, so the order for your wife’s 12 was just a regular order and not a pre-order.
Depending on when you ordered last Friday, however, there may not have been enough stock for delivery today. If you ordered as soon as preorders began at 5AM pacific time, then I would have expected delivery today, but if you ordered later in the day then it might not be delivered for another week or two. At the time you ordered it should have given you an expected delivery date. Apple is usually pretty good at making those dates and often phones are delivered even earlier than expected (but never before release day). If you look at your order online now you should see your expected delivery date.