Why is the Recents album on Iphone 13 Pro Max called like that when not the recent ones appear on top?

The photos in Recents are sorted by newest, just with the newest pictures at the bottom. There's no way to change the sorting of the Recents album, but you can for other albums with iOS 14 and later-

1. Go to an album, then tap the More button.
2. Tap Sort, then choose a sorting option, like Custom Order, Oldest to Newest, or Newest to Oldest.

Organize and find your photos on your iPhone, iPad, or iPod touch - Apple Support

You can submit feedback to Apple here - Product Feedback - Apple

As the Recents album always opens showing the photos at the bottom of the album, it would be highly inconvenient if the sorting were "Newest first". I would have to scroll fifty thousands photos up to get to the recents at the top of the album. If Apple changed the sorting of Recents from "Oldest first" to "Newest first", they would also have to change how the album is scrolled, when it is opened. As it is now, the most recent photos at the bottom of the album are shown, when the Recent album opens, so it is very convenient. And it is consist across all predefined albums - the ting is "oldest first"with the most recent photos at the bottom of the album and shown, when the album opens.

Well, like I said, you can submit feedback at the link I provided, but you aren't addressing Apple or Apple employees here. We are only fellow end users, volunteering our time to help others.