Can owners draft players directly to the Taxi Squad or the IR?

Commissioners can enable the draft to work this way by going to League » Settings » Configure Draft » Count players on Injured Reserve/Taxi Squad and setting both or either options to No. These settings will only be seen if Taxi Squad and IR positions have been added to the roster requirements. If commissioners don't change the setting prior to the draft, the default experience is to treat intended Taxi Squad players like any other players.