Does the VNAV descent profile consider that we're flying directly to the FI, therefore we're high?
Indeed, because from your description you have told the FMC you are flying a shortened route. If you were on VNAVPTH at the time of the change then informing the FMC you are flying s shorter distance will cause VNAV to calculate you are high; but you may not be and so it needs good SA to manage your descent path and remain in idle and on a sensible path.