I like the Untouchable mission (not as much as I do the other missions in the WoA, but I’m still a fan of it in its context in the trilogy and think it is a very fitting/suitable conclusion for the WoA) so I’m not here to touch on that, but just wanted to pick up on the quoted part of your post above.
Surely the main reason for the prolongued 6 year gap between Blood Money and Absolution was the construction of the new Glacier 2 game engine, and IOI’s mid-development-cycle decision to pivot from making a purely linear Gears Of War-style successor to Blood Money to a new direction where they tried [with limited success] to introduce some more traditional Hitman sandboxes back into the mix?
I’m pretty sure that Hakan Abrak has explicitly cited these as the main drivers for the gap between Blood Money and Absolution in interviews previously, and I don’t think Blood Money’s sales performance as a pure sandbox experience was as important a factor in this compared to IOI’s under-estimate of how long Glacier 2 development would take, and then the design-philosophy change-of-course that they tried to accomplish midway through making Absolution.