"Rate app-name" link goes to the app's App Store page, not the "write review" page

[ericbenwa]

Trying through TestFlight...
When I tap "Rate app-name", the screen that slides up is my app's App Store page.
Armchair is not bringing me to a Write Review screen which I thought would be the intended behavior.

Separately, in Xcode...
In the output window, Armchair provides a URL:
https://itunes.apple.com/us/app/id1488757440?ls=1&mt=8&at=11l7j9&ct=Armchair-1488757440&action=write-review

If I copy this URL and paste it into Safari on my iPhone, it'll correctly open to the Write Review screen

Why is this not working my I launch from the actual (TestFlight) app?
Is this just a TestFlight thing and once I go live it'll go to the proper destination?

Thanks!

iPhone 11 Pro
iOS 14.3