Take the screenshot > hit the checkbox > save to photos > open photos app > choose the first photo > select the text.
I guess it’s true that there is a lack of overlapping windows but other than that this process is very quick with very few button presses.
The situation should dictate the solution as decided by the user, instead of the OS dictating a solution and limiting options regardless of the situation.
The iPad can use apps in multiple floating windows, there’s no difference here. You don’t have to switch back and forth between apps.
You can even use a keyboard and mouse and the same copy paste keyboard shortcuts if you really want.
And I’m sure there are apps on the App Store to help this workflow in some way. The iPad isn’t some static device where you’re stuck with the software it comes with.