Any thoughts on why DJI is not making use of the DJI GO 4 app (which in my opinion is much more "professional" than this FLY-app) and another thought I have is that the standard remote has much less options (like adjusting aperture etc.) than the standard (!) remote the Mavic 2 has... and indeed.... WAYPOINTS... of course I can fly all paths I want, but using WAYPOINTS gives me this excellent possibility to adjust the camera when flying semi-autonomous...

I think the code was old and hard to maintain and they wanted a simpler app for the consumers.

Probably lots of legacy code that was hard (expensive) to work with.
It was introduced around 6 years ago. Lots of things have changed since then.
And I have to say I found the Go4 app a lot more cluttered than the Fly app.
So the visual part has improved if you ask me.
But a lot of features are still missing indeed.