That's obviously not true. There are 16 (XS/XF had 8) DUAL insert effects (A/B) available, one DUAL insert effect per part. What he is showing at 7:30 is the AWM2 Part Effect Routing page which lets you route each of the 8 ELEMENTS of one part through Insert A or B. Same functionality obviously exists in the XS/XF, but it's available in voice element edit. On Montage evidently the routing of all 8 elements in done in part common edit (which is pretty convenient).

There are Dual Insert Effects available for each of the sixteen Parts and a dedicated Dual Insert Effect for the A/D Input (which can be assigned to be controlled by your various controllers).

What Bert was showing was that each Element within an AWM2 Part can be routed to either Insert A or Insert B. The two Inserts, like on the XS/XF, can be run in parallel or in series. There is a 3-band EQ pre the Insert Effect block and a 2-band EQ post the Insert Effect block for each Part.