Hi Pavel

XPA3 is probably a wrap that encapsulates both old and new libraries. This is why it's almost double in size than it was
Major functionalities are still served by the old engine, and this is why you see old style screens appearing here and there in studio.
Unfortunately, MSE seems to be still in the process of replacing old parts with new ones, and this makes every new release a risk to adopt.

In my opinion XPA3 was prematurely released - at least two years earlier than it should be.
This has already put in high risk all the good fame that was built in the past by Magic.
Plus risking the careers and relations with clients of those who rushed to adopt the new version. 

Avgerinos