Why not a 1972/74 Monza layout?

In 1972/73 and 74 (I'm not sure about the following years), the F1 GP was contested on a route cut by two chicanes and not three as from the 80s. The first chicane, very simple , was placed just after the start/finish line. No chicane before the two Lesmo and the second chicane was located at the large left-hand curve called Ascari (very similar, in its layout, to the current chicane at the same location).
I thought it would be relatively easy (!) to offer us this route starting from the 1970 version of Monza already available in AMS2... Well "relatively easy" being debatable, I admit it!

 

Well some people (me) have also wondered why they haven’t added the Monza oval yet